Search Results

Search found 1120 results on 45 pages for 'simplest'.

Page 43/45 | < Previous Page | 39 40 41 42 43 44 45  | Next Page >

• Testing Workflows &ndash; Test-First

  - by Timothy Klenke

  Originally posted on: http://geekswithblogs.net/TimothyK/archive/2014/05/30/testing-workflows-ndash-test-first.aspxThis is the second of two posts on some common strategies for approaching the job of writing tests.  The previous post covered test-after workflows where as this will focus on test-first.  Each workflow presented is a method of attack for adding tests to a project.  The more tools in your tool belt the better.  So here is a partial list of some test-first methodologies. Ping Pong Ping Pong is a methodology commonly used in pair programing.  One developer will write a new failing test.  Then they hand the keyboard to their partner.  The partner writes the production code to get the test passing.  The partner then writes the next test before passing the keyboard back to the original developer. The reasoning behind this testing methodology is to facilitate pair programming.  That is to say that this testing methodology shares all the benefits of pair programming, including ensuring multiple team members are familiar with the code base (i.e. low bus number). Test Blazer Test Blazing, in some respects, is also a pairing strategy.  The developers don’t work side by side on the same task at the same time.  Instead one developer is dedicated to writing tests at their own desk.  They write failing test after failing test, never touching the production code.  With these tests they are defining the specification for the system.  The developer most familiar with the specifications would be assigned this task. The next day or later in the same day another developer fetches the latest test suite.  Their job is to write the production code to get those tests passing.  Once all the tests pass they fetch from source control the latest version of the test project to get the newer tests. This methodology has some of the benefits of pair programming, namely lowering the bus number.  This can be good way adding an extra developer to a project without slowing it down too much.  The production coder isn’t slowed down writing tests.  The tests are in another project from the production code, so there shouldn’t be any merge conflicts despite two developers working on the same solution. This methodology is also a good test for the tests.  Can another developer figure out what system should do just by reading the tests?  This question will be answered as the production coder works there way through the test blazer’s tests. Test Driven Development (TDD) TDD is a highly disciplined practice that calls for a new test and an new production code to be written every few minutes.  There are strict rules for when you should be writing test or production code.  You start by writing a failing (red) test, then write the simplest production code possible to get the code working (green), then you clean up the code (refactor).  This is known as the red-green-refactor cycle. The goal of TDD isn’t the creation of a suite of tests, however that is an advantageous side effect.  The real goal of TDD is to follow a practice that yields a better design.  The practice is meant to push the design toward small, decoupled, modularized components.  This is generally considered a better design that large, highly coupled ball of mud. TDD accomplishes this through the refactoring cycle.  Refactoring is only possible to do safely when tests are in place.  In order to use TDD developers must be trained in how to look for and repair code smells in the system.  Through repairing these sections of smelly code (i.e. a refactoring) the design of the system emerges. For further information on TDD, I highly recommend the series “Is TDD Dead?”.  It discusses its pros and cons and when it is best used. Acceptance Test Driven Development (ATDD) Whereas TDD focuses on small unit tests that concentrate on a small piece of the system, Acceptance Tests focuses on the larger integrated environment.  Acceptance Tests usually correspond to user stories, which come directly from the customer. The unit tests focus on the inputs and outputs of smaller parts of the system, which are too low level to be of interest to the customer. ATDD generally uses the same tools as TDD.  However, ATDD uses fewer mocks and test doubles than TDD. ATDD often complements TDD; they aren’t competing methods.  A full test suite will usually consist of a large number of unit (created via TDD) tests and a smaller number of acceptance tests. Behaviour Driven Development (BDD) BDD is more about audience than workflow.  BDD pushes the testing realm out towards the client.  Developers, managers and the client all work together to define the tests. Typically different tooling is used for BDD than acceptance and unit testing.  This is done because the audience is not just developers.  Tools using the Gherkin family of languages allow for test scenarios to be described in an English format.  Other tools such as MSpec or FitNesse also strive for highly readable behaviour driven test suites. Because these tests are public facing (viewable by people outside the development team), the terminology usually changes.  You can’t get away with the same technobabble you can with unit tests written in a programming language that only developers understand.  For starters, they usually aren’t called tests.  Usually they’re called “examples”, “behaviours”, “scenarios”, or “specifications”. This may seem like a very subtle difference, but I’ve seen this small terminology change have a huge impact on the acceptance of the process.  Many people have a bias that testing is something that comes at the end of a project.  When you say we need to define the tests at the start of the project many people will immediately give that a lower priority on the project schedule.  But if you say we need to define the specification or behaviour of the system before we can start, you’ll get more cooperation.   Keep these test-first and test-after workflows in your tool belt.  With them you’ll be able to find new opportunities to apply them.

  Read the article

• Organization &amp; Architecture UNISA Studies &ndash; Chap 4

  - by MarkPearl

  Learning Outcomes Explain the characteristics of memory systems Describe the memory hierarchy Discuss cache memory principles Discuss issues relevant to cache design Describe the cache organization of the Pentium Computer Memory Systems There are key characteristics of memory… Location – internal or external Capacity – expressed in terms of bytes Unit of Transfer – the number of bits read out of or written into memory at a time Access Method – sequential, direct, random or associative From a users perspective the two most important characteristics of memory are… Capacity Performance – access time, memory cycle time, transfer rate The trade off for memory happens along three axis… Faster access time, greater cost per bit Greater capacity, smaller cost per bit Greater capacity, slower access time This leads to people using a tiered approach in their use of memory   As one goes down the hierarchy, the following occurs… Decreasing cost per bit Increasing capacity Increasing access time Decreasing frequency of access of the memory by the processor The use of two levels of memory to reduce average access time works in principle, but only if conditions 1 to 4 apply. A variety of technologies exist that allow us to accomplish this. Thus it is possible to organize data across the hierarchy such that the percentage of accesses to each successively lower level is substantially less than that of the level above. A portion of main memory can be used as a buffer to hold data temporarily that is to be read out to disk. This is sometimes referred to as a disk cache and improves performance in two ways… Disk writes are clustered. Instead of many small transfers of data, we have a few large transfers of data. This improves disk performance and minimizes processor involvement. Some data designed for write-out may be referenced by a program before the next dump to disk. In that case the data is retrieved rapidly from the software cache rather than slowly from disk. Cache Memory Principles Cache memory is substantially faster than main memory. A caching system works as follows.. When a processor attempts to read a word of memory, a check is made to see if this in in cache memory… If it is, the data is supplied, If it is not in the cache, a block of main memory, consisting of a fixed number of words is loaded to the cache. Because of the phenomenon of locality of references, when a block of data is fetched into the cache, it is likely that there will be future references to that same memory location or to other words in the block. Elements of Cache Design While there are a large number of cache implementations, there are a few basic design elements that serve to classify and differentiate cache architectures… Cache Addresses Cache Size Mapping Function Replacement Algorithm Write Policy Line Size Number of Caches Cache Addresses Almost all non-embedded processors support virtual memory. Virtual memory in essence allows a program to address memory from a logical point of view without needing to worry about the amount of physical memory available. When virtual addresses are used the designer may choose to place the cache between the MMU (memory management unit) and the processor or between the MMU and main memory. The disadvantage of virtual memory is that most virtual memory systems supply each application with the same virtual memory address space (each application sees virtual memory starting at memory address 0), which means the cache memory must be completely flushed with each application context switch or extra bits must be added to each line of the cache to identify which virtual address space the address refers to. Cache Size We would like the size of the cache to be small enough so that the overall average cost per bit is close to that of main memory alone and large enough so that the overall average access time is close to that of the cache alone. Also, larger caches are slightly slower than smaller ones. Mapping Function Because there are fewer cache lines than main memory blocks, an algorithm is needed for mapping main memory blocks into cache lines. The choice of mapping function dictates how the cache is organized. Three techniques can be used… Direct – simplest technique, maps each block of main memory into only one possible cache line Associative – Each main memory block to be loaded into any line of the cache Set Associative – exhibits the strengths of both the direct and associative approaches while reducing their disadvantages For detailed explanations of each approach – read the text book (page 148 – 154) Replacement Algorithm For associative and set associating mapping a replacement algorithm is needed to determine which of the existing blocks in the cache must be replaced by a new block. There are four common approaches… LRU (Least recently used) FIFO (First in first out) LFU (Least frequently used) Random selection Write Policy When a block resident in the cache is to be replaced, there are two cases to consider If no writes to that block have happened in the cache – discard it If a write has occurred, a process needs to be initiated where the changes in the cache are propagated back to the main memory. There are several approaches to achieve this including… Write Through – all writes to the cache are done to the main memory as well at the point of the change Write Back – when a block is replaced, all dirty bits are written back to main memory The problem is complicated when we have multiple caches, there are techniques to accommodate for this but I have not summarized them. Line Size When a block of data is retrieved and placed in the cache, not only the desired word but also some number of adjacent words are retrieved. As the block size increases from very small to larger sizes, the hit ratio will at first increase because of the principle of locality, which states that the data in the vicinity of a referenced word are likely to be referenced in the near future. As the block size increases, more useful data are brought into cache. The hit ratio will begin to decrease as the block becomes even bigger and the probability of using the newly fetched information becomes less than the probability of using the newly fetched information that has to be replaced. Two specific effects come into play… Larger blocks reduce the number of blocks that fit into a cache. Because each block fetch overwrites older cache contents, a small number of blocks results in data being overwritten shortly after they are fetched. As a block becomes larger, each additional word is farther from the requested word and therefore less likely to be needed in the near future. The relationship between block size and hit ratio is complex, and no set approach is judged to be the best in all circumstances.   Pentium 4 and ARM cache organizations The processor core consists of four major components: Fetch/decode unit – fetches program instruction in order from the L2 cache, decodes these into a series of micro-operations, and stores the results in the L2 instruction cache Out-of-order execution logic – Schedules execution of the micro-operations subject to data dependencies and resource availability – thus micro-operations may be scheduled for execution in a different order than they were fetched from the instruction stream. As time permits, this unit schedules speculative execution of micro-operations that may be required in the future Execution units – These units execute micro-operations, fetching the required data from the L1 data cache and temporarily storing results in registers Memory subsystem – This unit includes the L2 and L3 caches and the system bus, which is used to access main memory when the L1 and L2 caches have a cache miss and to access the system I/O resources

  Read the article

• Parallelism in .NET – Part 2, Simple Imperative Data Parallelism

  - by Reed

  In my discussion of Decomposition of the problem space, I mentioned that Data Decomposition is often the simplest abstraction to use when trying to parallelize a routine.  If a problem can be decomposed based off the data, we will often want to use what MSDN refers to as Data Parallelism as our strategy for implementing our routine.  The Task Parallel Library in .NET 4 makes implementing Data Parallelism, for most cases, very simple. Data Parallelism is the main technique we use to parallelize a routine which can be decomposed based off data.  Data Parallelism refers to taking a single collection of data, and having a single operation be performed concurrently on elements in the collection.  One side note here: Data Parallelism is also sometimes referred to as the Loop Parallelism Pattern or Loop-level Parallelism.  In general, for this series, I will try to use the terminology used in the MSDN Documentation for the Task Parallel Library.  This should make it easier to investigate these topics in more detail. Once we’ve determined we have a problem that, potentially, can be decomposed based on data, implementation using Data Parallelism in the TPL is quite simple.  Let’s take our example from the Data Decomposition discussion – a simple contrast stretching filter.  Here, we have a collection of data (pixels), and we need to run a simple operation on each element of the pixel.  Once we know the minimum and maximum values, we most likely would have some simple code like the following: for (int row=0; row < pixelData.GetUpperBound(0); ++row) { for (int col=0; col < pixelData.GetUpperBound(1); ++col) { pixelData[row, col] = AdjustContrast(pixelData[row, col], minPixel, maxPixel); } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } This simple routine loops through a two dimensional array of pixelData, and calls the AdjustContrast routine on each pixel. As I mentioned, when you’re decomposing a problem space, most iteration statements are potentially candidates for data decomposition.  Here, we’re using two for loops – one looping through rows in the image, and a second nested loop iterating through the columns.  We then perform one, independent operation on each element based on those loop positions. This is a prime candidate – we have no shared data, no dependencies on anything but the pixel which we want to change.  Since we’re using a for loop, we can easily parallelize this using the Parallel.For method in the TPL: Parallel.For(0, pixelData.GetUpperBound(0), row => { for (int col=0; col < pixelData.GetUpperBound(1); ++col) { pixelData[row, col] = AdjustContrast(pixelData[row, col], minPixel, maxPixel); } }); Here, by simply changing our first for loop to a call to Parallel.For, we can parallelize this portion of our routine.  Parallel.For works, as do many methods in the TPL, by creating a delegate and using it as an argument to a method.  In this case, our for loop iteration block becomes a delegate creating via a lambda expression.  This lets you write code that, superficially, looks similar to the familiar for loop, but functions quite differently at runtime. We could easily do this to our second for loop as well, but that may not be a good idea.  There is a balance to be struck when writing parallel code.  We want to have enough work items to keep all of our processors busy, but the more we partition our data, the more overhead we introduce.  In this case, we have an image of data – most likely hundreds of pixels in both dimensions.  By just parallelizing our first loop, each row of pixels can be run as a single task.  With hundreds of rows of data, we are providing fine enough granularity to keep all of our processors busy. If we parallelize both loops, we’re potentially creating millions of independent tasks.  This introduces extra overhead with no extra gain, and will actually reduce our overall performance.  This leads to my first guideline when writing parallel code: Partition your problem into enough tasks to keep each processor busy throughout the operation, but not more than necessary to keep each processor busy. Also note that I parallelized the outer loop.  I could have just as easily partitioned the inner loop.  However, partitioning the inner loop would have led to many more discrete work items, each with a smaller amount of work (operate on one pixel instead of one row of pixels).  My second guideline when writing parallel code reflects this: Partition your problem in a way to place the most work possible into each task. This typically means, in practice, that you will want to parallelize the routine at the “highest” point possible in the routine, typically the outermost loop.  If you’re looking at parallelizing methods which call other methods, you’ll want to try to partition your work high up in the stack – as you get into lower level methods, the performance impact of parallelizing your routines may not overcome the overhead introduced. Parallel.For works great for situations where we know the number of elements we’re going to process in advance.  If we’re iterating through an IList<T> or an array, this is a typical approach.  However, there are other iteration statements common in C#.  In many situations, we’ll use foreach instead of a for loop.  This can be more understandable and easier to read, but also has the advantage of working with collections which only implement IEnumerable<T>, where we do not know the number of elements involved in advance. As an example, lets take the following situation.  Say we have a collection of Customers, and we want to iterate through each customer, check some information about the customer, and if a certain case is met, send an email to the customer and update our instance to reflect this change.  Normally, this might look something like: foreach(var customer in customers) { // Run some process that takes some time... DateTime lastContact = theStore.GetLastContact(customer); TimeSpan timeSinceContact = DateTime.Now - lastContact; // If it's been more than two weeks, send an email, and update... if (timeSinceContact.Days > 14) { theStore.EmailCustomer(customer); customer.LastEmailContact = DateTime.Now; } } Here, we’re doing a fair amount of work for each customer in our collection, but we don’t know how many customers exist.  If we assume that theStore.GetLastContact(customer) and theStore.EmailCustomer(customer) are both side-effect free, thread safe operations, we could parallelize this using Parallel.ForEach: Parallel.ForEach(customers, customer => { // Run some process that takes some time... DateTime lastContact = theStore.GetLastContact(customer); TimeSpan timeSinceContact = DateTime.Now - lastContact; // If it's been more than two weeks, send an email, and update... if (timeSinceContact.Days > 14) { theStore.EmailCustomer(customer); customer.LastEmailContact = DateTime.Now; } }); Just like Parallel.For, we rework our loop into a method call accepting a delegate created via a lambda expression.  This keeps our new code very similar to our original iteration statement, however, this will now execute in parallel.  The same guidelines apply with Parallel.ForEach as with Parallel.For. The other iteration statements, do and while, do not have direct equivalents in the Task Parallel Library.  These, however, are very easy to implement using Parallel.ForEach and the yield keyword. Most applications can benefit from implementing some form of Data Parallelism.  Iterating through collections and performing “work” is a very common pattern in nearly every application.  When the problem can be decomposed by data, we often can parallelize the workload by merely changing foreach statements to Parallel.ForEach method calls, and for loops to Parallel.For method calls.  Any time your program operates on a collection, and does a set of work on each item in the collection where that work is not dependent on other information, you very likely have an opportunity to parallelize your routine.

  Read the article

• Entity Association Mapping with Code First Part 1 : Mapping Complex Types

  - by mortezam

  Last week the CTP5 build of the new Entity Framework Code First has been released by data team at Microsoft. Entity Framework Code-First provides a pretty powerful code-centric way to work with the databases. When it comes to associations, it brings ultimate flexibility. I’m a big fan of the EF Code First approach and am planning to explain association mapping with code first in a series of blog posts and this one is dedicated to Complex Types. If you are new to Code First approach, you can find a great walkthrough here. In order to build a solid foundation for our discussion, we will start by learning about some of the core concepts around the relationship mapping.   What is Mapping?Mapping is the act of determining how objects and their relationships are persisted in permanent data storage, in our case, relational databases. What is Relationship mapping?A mapping that describes how to persist a relationship (association, aggregation, or composition) between two or more objects. Types of RelationshipsThere are two categories of object relationships that we need to be concerned with when mapping associations. The first category is based on multiplicity and it includes three types: One-to-one relationships: This is a relationship where the maximums of each of its multiplicities is one. One-to-many relationships: Also known as a many-to-one relationship, this occurs when the maximum of one multiplicity is one and the other is greater than one. Many-to-many relationships: This is a relationship where the maximum of both multiplicities is greater than one. The second category is based on directionality and it contains two types: Uni-directional relationships: when an object knows about the object(s) it is related to but the other object(s) do not know of the original object. To put this in EF terminology, when a navigation property exists only on one of the association ends and not on the both. Bi-directional relationships: When the objects on both end of the relationship know of each other (i.e. a navigation property defined on both ends). How Object Relationships Are Implemented in POCO domain models?When the multiplicity is one (e.g. 0..1 or 1) the relationship is implemented by defining a navigation property that reference the other object (e.g. an Address property on User class). When the multiplicity is many (e.g. 0..*, 1..*) the relationship is implemented via an ICollection of the type of other object. How Relational Database Relationships Are Implemented? Relationships in relational databases are maintained through the use of Foreign Keys. A foreign key is a data attribute(s) that appears in one table and must be the primary key or other candidate key in another table. With a one-to-one relationship the foreign key needs to be implemented by one of the tables. To implement a one-to-many relationship we implement a foreign key from the “one table” to the “many table”. We could also choose to implement a one-to-many relationship via an associative table (aka Join table), effectively making it a many-to-many relationship. Introducing the ModelNow, let's review the model that we are going to use in order to implement Complex Type with Code First. It's a simple object model which consist of two classes: User and Address. Each user could have one billing address. The Address information of a User is modeled as a separate class as you can see in the UML model below: In object-modeling terms, this association is a kind of aggregation—a part-of relationship. Aggregation is a strong form of association; it has some additional semantics with regard to the lifecycle of objects. In this case, we have an even stronger form, composition, where the lifecycle of the part is fully dependent upon the lifecycle of the whole. Fine-grained domain models The motivation behind this design was to achieve Fine-grained domain models. In crude terms, fine-grained means “more classes than tables”. For example, a user may have both a billing address and a home address. In the database, you may have a single User table with the columns BillingStreet, BillingCity, and BillingPostalCode along with HomeStreet, HomeCity, and HomePostalCode. There are good reasons to use this somewhat denormalized relational model (performance, for one). In our object model, we can use the same approach, representing the two addresses as six string-valued properties of the User class. But it’s much better to model this using an Address class, where User has the BillingAddress and HomeAddress properties. This object model achieves improved cohesion and greater code reuse and is more understandable. Complex Types: Splitting a Table Across Multiple Types Back to our model, there is no difference between this composition and other weaker styles of association when it comes to the actual C# implementation. But in the context of ORM, there is a big difference: A composed class is often a candidate Complex Type. But C# has no concept of composition—a class or property can’t be marked as a composition. The only difference is the object identifier: a complex type has no individual identity (i.e. no AddressId defined on Address class) which make sense because when it comes to the database everything is going to be saved into one single table. How to implement a Complex Types with Code First Code First has a concept of Complex Type Discovery that works based on a set of Conventions. The convention is that if Code First discovers a class where a primary key cannot be inferred, and no primary key is registered through Data Annotations or the fluent API, then the type will be automatically registered as a complex type. Complex type detection also requires that the type does not have properties that reference entity types (i.e. all the properties must be scalar types) and is not referenced from a collection property on another type. Here is the implementation: public class User{    public int UserId { get; set; }    public string FirstName { get; set; }    public string LastName { get; set; }    public string Username { get; set; }    public Address Address { get; set; }} public class Address {     public string Street { get; set; }     public string City { get; set; }            public string PostalCode { get; set; }        }public class EntityMappingContext : DbContext {     public DbSet<User> Users { get; set; }        } With code first, this is all of the code we need to write to create a complex type, we do not need to configure any additional database schema mapping information through Data Annotations or the fluent API. Database SchemaThe mapping result for this object model is as follows: Limitations of this mappingThere are two important limitations to classes mapped as Complex Types: Shared references is not possible: The Address Complex Type doesn’t have its own database identity (primary key) and so can’t be referred to by any object other than the containing instance of User (e.g. a Shipping class that also needs to reference the same User Address). No elegant way to represent a null reference There is no elegant way to represent a null reference to an Address. When reading from database, EF Code First always initialize Address object even if values in all mapped columns of the complex type are null. This means that if you store a complex type object with all null property values, EF Code First returns a initialized complex type when the owning entity object is retrieved from the database. SummaryIn this post we learned about fine-grained domain models which complex type is just one example of it. Fine-grained is fully supported by EF Code First and is known as the most important requirement for a rich domain model. Complex type is usually the simplest way to represent one-to-one relationships and because the lifecycle is almost always dependent in such a case, it’s either an aggregation or a composition in UML. In the next posts we will revisit the same domain model and will learn about other ways to map a one-to-one association that does not have the limitations of the complex types. References ADO.NET team blog Mapping Objects to Relational Databases Java Persistence with Hibernate

  Read the article

• How to deal with transport level security policy with OSB

  - by Jian Liang

  Recently, we received a use case for Oracle Service Bus (OSB) 11gPS4 to consume a Web Service which is secured by HTTP transport level security policy. The WSDL of the remote web service looks like following where the part marked in red shows the security policy: <?xml version='1.0' encoding='UTF-8'?> <definitions xmlns:wssutil="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-utility-1.0.xsd" xmlns:wsp="http://schemas.xmlsoap.org/ws/2004/09/policy" xmlns:soap="http://schemas.xmlsoap.org/wsdl/soap/" xmlns:tns="https://httpsbasicauth" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="http://schemas.xmlsoap.org/wsdl/" targetNamespace="https://httpsbasicauth" name="HttpsBasicAuthService"> <wsp:UsingPolicy wssutil:Required="true"/> <wsp:Policy wssutil:Id="WSHttpBinding_IPartyServicePortType_policy"> <wsp:ExactlyOne> <wsp:All> <ns1:TransportBinding xmlns:ns1="http://schemas.xmlsoap.org/ws/2005/07/securitypolicy"> <wsp:Policy> <ns1:TransportToken> <wsp:Policy> <ns1:HttpsToken RequireClientCertificate="false"/> </wsp:Policy> </ns1:TransportToken> <ns1:AlgorithmSuite> <wsp:Policy> <ns1:Basic256/> </wsp:Policy> </ns1:AlgorithmSuite> <ns1:Layout> <wsp:Policy> <ns1:Strict/> </wsp:Policy> </ns1:Layout> </wsp:Policy> </ns1:TransportBinding> <ns2:UsingAddressing xmlns:ns2="http://www.w3.org/2006/05/addressing/wsdl"/> </wsp:All> </wsp:ExactlyOne> </wsp:Policy> <types> <xsd:schema> <xsd:import namespace="https://proxyhttpsbasicauth" schemaLocation="http://localhost:7001/WS/HttpsBasicAuthService?xsd=1"/> </xsd:schema> <xsd:schema> <xsd:import namespace="https://httpsbasicauth" schemaLocation="http://localhost:7001/WS/HttpsBasicAuthService?xsd=2"/> </xsd:schema> </types> <message name="echoString"> <part name="parameters" element="tns:echoString"/> </message> <message name="echoStringResponse"> <part name="parameters" element="tns:echoStringResponse"/> </message> <portType name="HttpsBasicAuth"> <operation name="echoString"> <input message="tns:echoString"/> <output message="tns:echoStringResponse"/> </operation> </portType> <binding name="HttpsBasicAuthSoapPortBinding" type="tns:HttpsBasicAuth"> <wsp:PolicyReference URI="#WSHttpBinding_IPartyServicePortType_policy"/> <soap:binding transport="http://schemas.xmlsoap.org/soap/http" style="document"/> <operation name="echoString"> <soap:operation soapAction=""/> <input> <soap:body use="literal"/> </input> <output> <soap:body use="literal"/> </output> </operation> </binding> <service name="HttpsBasicAuthService"> <port name="HttpsBasicAuthSoapPort" binding="tns:HttpsBasicAuthSoapPortBinding"> <soap:address location="https://localhost:7002/WS/HttpsBasicAuthService"/> </port> </service> </definitions> The security assertion in the WSDL (marked in red) indicates that this is the HTTP transport level security policy which requires one way SSL with default authentication (aka. basic authenticate with username/password). Normally, there are two ways to handle web service security policy with OSB 11g: Use WebLogic 9.x policy Use OWSM Since OSB doesn’t support WebLogic 9.x WSSP transport level assertion (except for WS transport), when we tried to create the business service based on the imported WSDL, OSB complained with the following message: [OSB Kernel:398133]The service is based on WSDL with Web Services Security Policies that are not natively supported by Oracle Service Bus. Please select OWSM Policies - From OWSM Policy Store option and attach equivalent OWSM security policy. For the Business Service, either you can add the necessary client policies manually by clicking Add button or you can let Oracle Service Bus automatically pick and add compatible client policies by clicking Add Compatible button. Unfortunately, when tried with OWSM, we couldn’t find http_token_policy from OWSM since OSB PS4 doesn’t support OWSM http_token_policy. It seems that we ran into an unsupported situation that no appropriate policy can be used from both WebLogic and OWSM. As this security policy requires one way SSL with basic authentication at the transport level, a possible workaround is to meet the remote service's requirement at transport level without using web service policy. We can simply use OSB to establish SSL connection and provide username/password for authentication at the transport level to the remote web service. In this case, the business service within OSB will be transparent to the web service policy. However, we still need to deal with OSB console’s complaint related to unsupported security policy because the failure of WSDL validation prohibits OSB console to move forward. With the help from OSB Product Management team, we finally came up with the following solutions: Solution 1: OSB PS5 The good news is that the http_token_policy is made available in OSB PS5. With OSB PS5, you can simply add OWSM oracle/wss_http_token_over_ssl_client_policy to the business service. The simplest solution is to upgrade to OSB PS5 where the OWSM solution is provided out of the box. But if you are not in a position where upgrading is an immediate option, you might want to consider other two workaround solutions described below. Solution 2: Modifying WSDL This solution addresses OSB console’s complaint by removing the security policy from the imported WSDL within OSB. Without the security policy, OSB console allows the business service to be created based on modified WSDL.  Please bear in mind, modifying WSDL is done only for the OSB side via OSB console, no change is required on the remote Web Service. The main steps of this solution: Connect to OSB console import the remote WSDL into OSB remove security assertion (the red marked part) from the imported WSDL create a service account. In our sample, we simply take the user weblogic create the business service and check "Basic" for Authentication and select the created service account make sure that OSB consumes the web service via https. This solution requires modifying WSDL. It is suitable for any OSB version (10g or OSB 11g version) prior to PS5 without OWSM. However, modifying WSDL by hand is troublesome as it requires the user to remember that the original WSDL was edited.  It forces you to make the same edit each time you want to re-import the service WSDL when changes occur at the service level. This also prevents you from using UDDI to import WSDL.  Solution 3: Using original WSDL This solution keeps the WSDL intact and ignores the embedded policy by using OWSM. By design, OWSM doesn’t like WSDL with embedded security assertion. Since OWSM doesn’t provide the feature to explicitly ignore the embedded policy from a remote WSDL, in this solution, we use OWSM in a tricky way to ignore the embedded policy. Connect to OSB console import the remote WSDL into OSB create a service account create the business service in which check "Basic" for Authentication and select the created service account as the imported WSDL is intact, the OSB Kernel:398133 error is expected ignore this error message for the moment and navigate to the Policies Page of business service Select “From OWSM Policy Store” and click “Add” button, the list of policies will pop-up Here is the tricky part: select an arbitrary policy, and click “Cancel” Update and save By clicking “Cancel’ button, we didn’t add any OWSM policy to business service, but the embedded policy is ignored. Yes, this is tricky. According to Oracle OSB Product Manager, the future release of OWSM will add a button “None” which allows to ignore the embedded policy explicitly. This solution keeps the imported WSDL intact which is the big advantage over the solution 2. It is suitable for OSB 11g (version prior to PS5) domain with OWSM configured. This blog addressed the unsupported transport level web service security policy with OSB PS4. To summarize, if you are using OSB PS5 or in a position to upgrade to PS5, the recommendation is to use OWSM OOTB transport level security policy directly. With the release prior to 11g PS5, you can consider the solution 2 or 3 depending on if OWSM is configured.

  Read the article

• ASP.NET MVC Postbacks and HtmlHelper Controls ignoring Model Changes

  - by Rick Strahl

  So here's a binding behavior in ASP.NET MVC that I didn't really get until today: HtmlHelpers controls (like .TextBoxFor() etc.) don't bind to model values on Postback, but rather get their value directly out of the POST buffer from ModelState. Effectively it looks like you can't change the display value of a control via model value updates on a Postback operation. To demonstrate here's an example. I have a small section in a document where I display an editable email address: This is what the form displays on a GET operation and as expected I get the email value displayed in both the textbox and plain value display below, which reflects the value in the mode. I added a plain text value to demonstrate the model value compared to what's rendered in the textbox. The relevant markup is the email address which needs to be manipulated via the model in the Controller code. Here's the Razor markup: <div class="fieldcontainer"> <label> Email: &nbsp; <small>(username and <a href="http://gravatar.com">Gravatar</a> image)</small> </label> <div> @Html.TextBoxFor( mod=> mod.User.Email, new {type="email",@class="inputfield"}) @Model.User.Email </div> </div>   So, I have this form and the user can change their email address. On postback the Post controller code then asks the business layer whether the change is allowed. If it's not I want to reset the email address back to the old value which exists in the database and was previously store. The obvious thing to do would be to modify the model. Here's the Controller logic block that deals with that:// did user change email? if (!string.IsNullOrEmpty(oldEmail) && user.Email != oldEmail) { if (userBus.DoesEmailExist(user.Email)) { userBus.ValidationErrors.Add("New email address exists already. Please…"); user.Email = oldEmail; } else // allow email change but require verification by forcing a login user.IsVerified = false; }… model.user = user; return View(model); The logic is straight forward - if the new email address is not valid because it already exists I don't want to display the new email address the user entered, but rather the old one. To do this I change the value on the model which effectively does this:model.user.Email = oldEmail; return View(model); So when I press the Save button after entering in my new email address ([email protected]) here's what comes back in the rendered view: Notice that the textbox value and the raw displayed model value are different. The TextBox displays the POST value, the raw value displays the actual model value which are different. This means that MVC renders the textbox value from the POST data rather than from the view data when an Http POST is active. Now I don't know about you but this is not the behavior I expected - initially. This behavior effectively means that I cannot modify the contents of the textbox from the Controller code if using HtmlHelpers for binding. Updating the model for display purposes in a POST has in effect - no effect. (Apr. 25, 2012 - edited the post heavily based on comments and more experimentation) What should the behavior be? After getting quite a few comments on this post I quickly realized that the behavior I described above is actually the behavior you'd want in 99% of the binding scenarios. You do want to get the POST values back into your input controls at all times, so that the data displayed on a form for the user matches what they typed. So if an error occurs, the error doesn't mysteriously disappear getting replaced either with a default value or some value that you changed on the model on your own. Makes sense. Still it is a little non-obvious because the way you create the UI elements with MVC, it certainly looks like your are binding to the model value:@Html.TextBoxFor( mod=> mod.User.Email, new {type="email",@class="inputfield",required="required" }) and so unless one understands a little bit about how the model binder works this is easy to trip up. At least it was for me. Even though I'm telling the control which model value to bind to, that model value is only used initially on GET operations. After that ModelState/POST values provide the display value. Workarounds The default behavior should be fine for 99% of binding scenarios. But if you do need fix up values based on your model rather than the default POST values, there are a number of ways that you can work around this. Initially when I ran into this, I couldn't figure out how to set the value using code and so the simplest solution to me was simply to not use the MVC Html Helper for the specific control and explicitly bind the model via HTML markup and @Razor expression: <input type="text" name="User.Email" id="User_Email" value="@Model.User.Email" /> And this produces the right result. This is easy enough to create, but feels a little out of place when using the @Html helpers for everything else. As you can see by the difference in the name and id values, you also are forced to remember the naming conventions that MVC imposes in order for ModelBinding to work properly which is a pain to remember and set manually (name is the same as the property with . syntax, id replaces dots with underlines). Use the ModelState Some of my original confusion came because I didn't understand how the model binder works. The model binder basically maintains ModelState on a postback, which holds a value and binding errors for each of the Post back value submitted on the page that can be mapped to the model. In other words there's one ModelState entry for each bound property of the model. Each ModelState entry contains a value property that holds AttemptedValue and RawValue properties. The AttemptedValue is essentially the POST value retrieved from the form. The RawValue is the value that the model holds. When MVC binds controls like @Html.TextBoxFor() or @Html.TextBox(), it always binds values on a GET operation. On a POST operation however, it'll always used the AttemptedValue to display the control. MVC binds using the ModelState on a POST operation, not the model's value. So, if you want the behavior that I was expecting originally you can actually get it by clearing the ModelState in the controller code:ModelState.Clear(); This clears out all the captured ModelState values, and effectively binds to the model. Note this will produce very similar results - in fact if there are no binding errors you see exactly the same behavior as if binding from ModelState, because the model has been updated from the ModelState already and binding to the updated values most likely produces the same values you would get with POST back values. The big difference though is that any values that couldn't bind - like say putting a string into a numeric field - will now not display back the value the user typed, but the default field value or whatever you changed the model value to. This is the behavior I was actually expecting previously. But - clearing out all values might be a bit heavy handed. You might want to fix up one or two values in a model but rarely would you want the entire model to update from the model. So, you can also clear out individual values on an as needed basis:if (userBus.DoesEmailExist(user.Email)) { userBus.ValidationErrors.Add("New email address exists already. Please…"); user.Email = oldEmail; ModelState.Remove("User.Email"); } This allows you to remove a single value from the ModelState and effectively allows you to replace that value for display from the model. Why? While researching this I came across a post from Microsoft's Brad Wilson who describes the default binding behavior best in a forum post: The reason we use the posted value for editors rather than the model value is that the model may not be able to contain the value that the user typed. Imagine in your "int" editor the user had typed "dog". You want to display an error message which says "dog is not valid", and leave "dog" in the editor field. However, your model is an int: there's no way it can store "dog". So we keep the old value. If you don't want the old values in the editor, clear out the Model State. That's where the old value is stored and pulled from the HTML helpers. There you have it. It's not the most intuitive behavior, but in hindsight this behavior does make some sense even if at first glance it looks like you should be able to update values from the model. The solution of clearing ModelState works and is a reasonable one but you have to know about some of the innards of ModelState and how it actually works to figure that out.© Rick Strahl, West Wind Technologies, 2005-2012Posted in ASP.NET  MVC   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

  Read the article

• Data Profiling without SSIS

  Strangely enough for a predominantly SSIS blog, this post is all about how to perform data profiling without using SSIS. Whilst the Data Profiling Task is a worthy addition, there are a couple of limitations I’ve encountered of late. The first is that it requires SQL Server 2008, and not everyone is there yet. The second is that it can only target SQL Server 2005 and above. What about older systems, which are the ones that we probably need to investigate the most, or other vendor databases such as Oracle? With these limitations in mind I did some searching to find a quick and easy alternative to help me perform some data profiling for a project I was working on recently. I only had SQL Server 2005 available, and anyway most of my target source systems were Oracle, and of course I had short timescales. I looked at several options. Some never got beyond the download stage, they failed to install or just did not run, and others provided less than I could have produced myself by spending 2 minutes writing some basic SQL queries. In the end I settled on an open source product called DataCleaner. To quote from their website: DataCleaner is an Open Source application for profiling, validating and comparing data. These activities help you administer and monitor your data quality in order to ensure that your data is useful and applicable to your business situation. DataCleaner is the free alternative to software for master data management (MDM) methodologies, data warehousing (DW) projects, statistical research, preparation for extract-transform-load (ETL) activities and more. DataCleaner is developed in Java and licensed under LGPL. As quoted above it claims to support profiling, validating and comparing data, but I didn’t really get past the profiling functions, so won’t comment on the other two. The profiling whilst not prefect certainly saved some time compared to the limited alternatives. The ability to profile heterogeneous data sources is a big advantage over the SSIS option, and I found it overall quite easy to use and performance was good. I could see it struggling at times, but actually for what it does I was impressed. It had some data type niggles with Oracle, and some metrics seem a little strange, although thankfully they were easy to augment with some SQL queries to ensure a consistent picture. The report export options didn’t do it for me, but copy and paste with a bit of Excel magic was sufficient. One initial point for me personally is that I have had limited exposure to things of the Java persuasion and whilst I normally get by fine, sometimes the simplest things can throw me. For example installing a JDBC driver, why do I have to copy files to make it all work, has nobody ever heard of an MSI? In case there are other people out there like me who have become totally indoctrinated with the Microsoft software paradigm, I’ve written a quick start guide that details every step required. Steps 1- 5 are the key ones, the rest is really an excuse for some screenshots to show you the tool. Quick Start Guide Step 1  - Download Data Cleaner. The Microsoft Windows zipped exe option, and I chose the latest stable build, currently DataCleaner 1.5.3 (final). Extract the files to a suitable location. Step 2 - Download Java. If you try and run datacleaner.exe without Java it will warn you, and then open your default browser and take you to the Java download site. Follow the installation instructions from there, normally just click Download Java a couple of times and you’re done. Step 3 - Download Microsoft SQL Server JDBC Driver. You may have SQL Server installed, but you won’t have a JDBC driver. Version 3.0 is the latest as of April 2010. There is no real installer, we are in the Java world here, but run the exe you downloaded to extract the files. The default Unzip to folder is not much help, so try a fully qualified path such as C:\Program Files\Microsoft SQL Server JDBC Driver 3.0\ to ensure you can find the files afterwards. Step 4 - If you wish to use Windows Authentication to connect to your SQL Server then first we need to copy a file so that Data Cleaner can find it. Browse to the JDBC extract location from Step 3 and drill down to the file sqljdbc_auth.dll. You will have to choose the correct directory for your processor architecture. e.g. C:\Program Files\Microsoft SQL Server JDBC Driver 3.0\sqljdbc_3.0\enu\auth\x86\sqljdbc_auth.dll. Now copy this file to the Data Cleaner extract folder you chose in Step 1. An alternative method is to edit datacleaner.cmd in the data cleaner extract folder as detailed in this data cleaner wiki topic, but I find copying the file simpler. Step 5 – Now lets run Data Cleaner, just run datacleaner.exe from the extract folder you chose in Step 1. Step 6 – Complete or skip the registration screen, and ignore the task window for now. In the main window click settings. Step 7 – In the Settings dialog, select the Database drivers tab, then click Register database driver and select the Local JAR file option. Step 8 – Browse to the JDBC driver extract location from Step 3 and drill down to select sqljdbc4.jar. e.g. C:\Program Files\Microsoft SQL Server JDBC Driver 3.0\sqljdbc_3.0\enu\sqljdbc4.jar Step 9 – Select the Database driver class as com.microsoft.sqlserver.jdbc.SQLServerDriver, and then click the Test and Save database driver button. Step 10 - You should be back at the Settings dialog with a the list of drivers that includes SQL Server. Just click Save Settings to persist all your hard work. Step 11 – Now we can start to profile some data. In the main Data Cleaner window click New Task, and then Profile from the task window. Step 12 – In the Profile window click Open Database Step 13 – Now choose the SQL Server connection string option. Selecting a connection string gives us a template like jdbc:sqlserver://<hostname>:1433;databaseName=<database>, but obviously it requires some details to be entered for example  jdbc:sqlserver://localhost:1433;databaseName=SQLBits. This will connect to the database called SQLBits on my local machine. The port may also have to be changed if using such as when you have a multiple instances of SQL Server running. If using SQL Server Authentication enter a username and password as required and then click Connect to database. You can use Window Authentication, just add integratedSecurity=true to the end of your connection string. e.g jdbc:sqlserver://localhost:1433;databaseName=SQLBits;integratedSecurity=true.  If you didn’t complete Step 4 above you will need to do so now and restart Data Cleaner before it will work. Manually setting the connection string is fine, but creating a named connection makes more sense if you will be spending any length of time profiling a specific database. As highlighted in the left-hand screen-shot, at the bottom of the dialog it includes partial instructions on how to create named connections. In the folder shown C:\Users\<Username>\.datacleaner\1.5.3, open the datacleaner-config.xml file in your editor of choice add your own details. You’ll see a sample connection in the file already, just add yours following the same pattern. e.g. <!-- Darren's Named Connections --> <bean class="dk.eobjects.datacleaner.gui.model.NamedConnection"> <property name="name" value="SQLBits Local Connection" /> <property name="driverClass" value="com.microsoft.sqlserver.jdbc.SQLServerDriver" /> <property name="connectionString" value="jdbc:sqlserver://localhost:1433;databaseName=SQLBits;integratedSecurity=true" /> <property name="tableTypes"> <list> <value>TABLE</value> <value>VIEW</value> </list> </property> </bean> Step 14 – Once back at the Profile window, you should now see your schemas, tables and/or views listed down the left hand side. Browse this tree and double-click a table to select it for profiling. You can then click Add profile, and choose some profiling options, before finally clicking Run profiling. You can see below a sample output for three of the most common profiles, click the image for full size.   I hope this has given you a taster for DataCleaner, and should help you get up and running pretty quickly.

  Read the article

• How to Reuse Your Old Wi-Fi Router as a Network Switch

  - by Jason Fitzpatrick

  Just because your old Wi-Fi router has been replaced by a newer model doesn’t mean it needs to gather dust in the closet. Read on as we show you how to take an old and underpowered Wi-Fi router and turn it into a respectable network switch (saving your $20 in the process). Image by mmgallan. Why Do I Want To Do This? Wi-Fi technology has changed significantly in the last ten years but Ethernet-based networking has changed very little. As such, a Wi-Fi router with 2006-era guts is lagging significantly behind current Wi-Fi router technology, but the Ethernet networking component of the device is just as useful as ever; aside from potentially being only 100Mbs instead of 1000Mbs capable (which for 99% of home applications is irrelevant) Ethernet is Ethernet. What does this matter to you, the consumer? It means that even though your old router doesn’t hack it for your Wi-Fi needs any longer the device is still a perfectly serviceable (and high quality) network switch. When do you need a network switch? Any time you want to share an Ethernet cable among multiple devices, you need a switch. For example, let’s say you have a single Ethernet wall jack behind your entertainment center. Unfortunately you have four devices that you want to link to your local network via hardline including your smart HDTV, DVR, Xbox, and a little Raspberry Pi running XBMC. Instead of spending $20-30 to purchase a brand new switch of comparable build quality to your old Wi-Fi router it makes financial sense (and is environmentally friendly) to invest five minutes of your time tweaking the settings on the old router to turn it from a Wi-Fi access point and routing tool into a network switch–perfect for dropping behind your entertainment center so that your DVR, Xbox, and media center computer can all share an Ethernet connection. What Do I Need? For this tutorial you’ll need a few things, all of which you likely have readily on hand or are free for download. To follow the basic portion of the tutorial, you’ll need the following: 1 Wi-Fi router with Ethernet ports 1 Computer with Ethernet jack 1 Ethernet cable For the advanced tutorial you’ll need all of those things, plus: 1 copy of DD-WRT firmware for your Wi-Fi router We’re conducting the experiment with a Linksys WRT54GL Wi-Fi router. The WRT54 series is one of the best selling Wi-Fi router series of all time and there’s a good chance a significant number of readers have one (or more) of them stuffed in an office closet. Even if you don’t have one of the WRT54 series routers, however, the principles we’re outlining here apply to all Wi-Fi routers; as long as your router administration panel allows the necessary changes you can follow right along with us. A quick note on the difference between the basic and advanced versions of this tutorial before we proceed. Your typical Wi-Fi router has 5 Ethernet ports on the back: 1 labeled “Internet”, “WAN”, or a variation thereof and intended to be connected to your DSL/Cable modem, and 4 labeled 1-4 intended to connect Ethernet devices like computers, printers, and game consoles directly to the Wi-Fi router. When you convert a Wi-Fi router to a switch, in most situations, you’ll lose two port as the “Internet” port cannot be used as a normal switch port and one of the switch ports becomes the input port for the Ethernet cable linking the switch to the main network. This means, referencing the diagram above, you’d lose the WAN port and LAN port 1, but retain LAN ports 2, 3, and 4 for use. If you only need to switch for 2-3 devices this may be satisfactory. However, for those of you that would prefer a more traditional switch setup where there is a dedicated WAN port and the rest of the ports are accessible, you’ll need to flash a third-party router firmware like the powerful DD-WRT onto your device. Doing so opens up the router to a greater degree of modification and allows you to assign the previously reserved WAN port to the switch, thus opening up LAN ports 1-4. Even if you don’t intend to use that extra port, DD-WRT offers you so many more options that it’s worth the extra few steps. Preparing Your Router for Life as a Switch Before we jump right in to shutting down the Wi-Fi functionality and repurposing your device as a network switch, there are a few important prep steps to attend to. First, you want to reset the router (if you just flashed a new firmware to your router, skip this step). Following the reset procedures for your particular router or go with what is known as the “Peacock Method” wherein you hold down the reset button for thirty seconds, unplug the router and wait (while still holding the reset button) for thirty seconds, and then plug it in while, again, continuing to hold down the rest button. Over the life of a router there are a variety of changes made, big and small, so it’s best to wipe them all back to the factory default before repurposing the router as a switch. Second, after resetting, we need to change the IP address of the device on the local network to an address which does not directly conflict with the new router. The typical default IP address for a home router is 192.168.1.1; if you ever need to get back into the administration panel of the router-turned-switch to check on things or make changes it will be a real hassle if the IP address of the device conflicts with the new home router. The simplest way to deal with this is to assign an address close to the actual router address but outside the range of addresses that your router will assign via the DHCP client; a good pick then is 192.168.1.2. Once the router is reset (or re-flashed) and has been assigned a new IP address, it’s time to configure it as a switch. Basic Router to Switch Configuration If you don’t want to (or need to) flash new firmware onto your device to open up that extra port, this is the section of the tutorial for you: we’ll cover how to take a stock router, our previously mentioned WRT54 series Linksys, and convert it to a switch. Hook the Wi-Fi router up to the network via one of the LAN ports (consider the WAN port as good as dead from this point forward, unless you start using the router in its traditional function again or later flash a more advanced firmware to the device, the port is officially retired at this point). Open the administration control panel via  web browser on a connected computer. Before we get started two things: first,  anything we don’t explicitly instruct you to change should be left in the default factory-reset setting as you find it, and two, change the settings in the order we list them as some settings can’t be changed after certain features are disabled. To start, let’s navigate to Setup ->Basic Setup. Here you need to change the following things: Local IP Address: [different than the primary router, e.g. 192.168.1.2] Subnet Mask: [same as the primary router, e.g. 255.255.255.0] DHCP Server: Disable Save with the “Save Settings” button and then navigate to Setup -> Advanced Routing: Operating Mode: Router This particular setting is very counterintuitive. The “Operating Mode” toggle tells the device whether or not it should enable the Network Address Translation (NAT)  feature. Because we’re turning a smart piece of networking hardware into a relatively dumb one, we don’t need this feature so we switch from Gateway mode (NAT on) to Router mode (NAT off). Our next stop is Wireless -> Basic Wireless Settings: Wireless SSID Broadcast: Disable Wireless Network Mode: Disabled After disabling the wireless we’re going to, again, do something counterintuitive. Navigate to Wireless -> Wireless Security and set the following parameters: Security Mode: WPA2 Personal WPA Algorithms: TKIP+AES WPA Shared Key: [select some random string of letters, numbers, and symbols like JF#d$di!Hdgio890] Now you may be asking yourself, why on Earth are we setting a rather secure Wi-Fi configuration on a Wi-Fi router we’re not going to use as a Wi-Fi node? On the off chance that something strange happens after, say, a power outage when your router-turned-switch cycles on and off a bunch of times and the Wi-Fi functionality is activated we don’t want to be running the Wi-Fi node wide open and granting unfettered access to your network. While the chances of this are next-to-nonexistent, it takes only a few seconds to apply the security measure so there’s little reason not to. Save your changes and navigate to Security ->Firewall. Uncheck everything but Filter Multicast Firewall Protect: Disable At this point you can save your changes again, review the changes you’ve made to ensure they all stuck, and then deploy your “new” switch wherever it is needed. Advanced Router to Switch Configuration For the advanced configuration, you’ll need a copy of DD-WRT installed on your router. Although doing so is an extra few steps, it gives you a lot more control over the process and liberates an extra port on the device. Hook the Wi-Fi router up to the network via one of the LAN ports (later you can switch the cable to the WAN port). Open the administration control panel via web browser on the connected computer. Navigate to the Setup -> Basic Setup tab to get started. In the Basic Setup tab, ensure the following settings are adjusted. The setting changes are not optional and are required to turn the Wi-Fi router into a switch. WAN Connection Type: Disabled Local IP Address: [different than the primary router, e.g. 192.168.1.2] Subnet Mask: [same as the primary router, e.g. 255.255.255.0] DHCP Server: Disable In addition to disabling the DHCP server, also uncheck all the DNSMasq boxes as the bottom of the DHCP sub-menu. If you want to activate the extra port (and why wouldn’t you), in the WAN port section: Assign WAN Port to Switch [X] At this point the router has become a switch and you have access to the WAN port so the LAN ports are all free. Since we’re already in the control panel, however, we might as well flip a few optional toggles that further lock down the switch and prevent something odd from happening. The optional settings are arranged via the menu you find them in. Remember to save your settings with the save button before moving onto a new tab. While still in the Setup -> Basic Setup menu, change the following: Gateway/Local DNS : [IP address of primary router, e.g. 192.168.1.1] NTP Client : Disable The next step is to turn off the radio completely (which not only kills the Wi-Fi but actually powers the physical radio chip off). Navigate to Wireless -> Advanced Settings -> Radio Time Restrictions: Radio Scheduling: Enable Select “Always Off” There’s no need to create a potential security problem by leaving the Wi-Fi radio on, the above toggle turns it completely off. Under Services -> Services: DNSMasq : Disable ttraff Daemon : Disable Under the Security -> Firewall tab, uncheck every box except “Filter Multicast”, as seen in the screenshot above, and then disable SPI Firewall. Once you’re done here save and move on to the Administration tab. Under Administration -> Management:  Info Site Password Protection : Enable Info Site MAC Masking : Disable CRON : Disable 802.1x : Disable Routing : Disable After this final round of tweaks, save and then apply your settings. Your router has now been, strategically, dumbed down enough to plod along as a very dependable little switch. Time to stuff it behind your desk or entertainment center and streamline your cabling.     

  Read the article

• CodePlex Daily Summary for Tuesday, March 30, 2010

  CodePlex Daily Summary for Tuesday, March 30, 2010New ProjectsCloudMail: Want to send email from Azure? Cloud Mail is designed to provide a small, effective and reliable solution for sending email from the Azure platfor...CommunityServer Extensions: Here you can find some CommunityServer extensions and bug fixes. The main goal is to provide you with the ability to correct some common problems...ContactSync: ContactSync is a set of .NET libraries, UI controls and applications for managing and synchronizing contact information. It includes managed wrapp...Dng portal: DNG Portal base on asp.net MVCDotNetNuke Referral Tracker: The Referral Tracker module allows you to save URL variables, the referring page, and the previous page into a session variable or cookie. Then, th...Foursquare for Windows Phone 7: Foursquare for Windows Phone 7.GEGetDocConfig: SharePoint utility to list information concerning document libraries in one or more sites. Displays Size, Validity, Folder, Parent, Author, Minor a...Google Maps API for .NET: Fast and lightweight client libraries for Google Maps API.kbcchina: kbc chinaLoad Test User Mock Toolkits: 用途 This project is a framework mocking the user actvities with VSTS Load Test tool to faster the test script development. 此项目包括一套模拟用户行为的通用框架，可以简化...Resonance: Resonance is a system to train neural networks, it allows to automate the train of a neural network, distributing the calculation on multiple machi...SharePoint Company Directory / Active Directory Self Service System: This is a very simple system which was designed for a Bank to allow users to update their contact information within SharePoint . Then this info ca...SmartShelf: Manage files and folders on Windows and Windows Live.sysFix: sysFix is a tool for system administrators to easily manage and fix common system errors.xnaWebcam: Webcam usage in XNA GameStudio 3.1New ReleasesAll-In-One Code Framework: All-In-One Code Framework 2010-03-29: Improved and Newly Added Examples:For an up-to-date list, please refer to All-In-One Code Framework Sample Catalog. Samples for Azure Name Des...ARSoft.Tools.Net - C# DNS and SPF Library: 1.3.0: Added support for creating own dns server implementations. Added full IPv6 support to dns client Some performance optimizations to dns clientArtefact Animator: Artefact Animator - Silverlight 3 and WPF .Net 3.5: Artefact Animator Version 2.0.4.1 Silverlight 3 ArtefactSL.dll for both Debug and Release. WPF 3.5 Artefact.dll for both Debug and Release.BatterySaver: Version 0.4: Added support for a system tray icon for controlling the application and switching profiles (Issue)BizTalk Server 2006 Orchestration Profiler: Profiler v1.2: This is a point release of the profiler and has been updatd to work on 64 bit systems. No other new functionality is available. To use this ensure...CloudMail: CloudMail_0.5_beta: Initial public release. For documentation see http://cloudmail.codeplex.com/documentation.CycleMania Starter Kit EAP - ASP.NET 4 Problem - Design - Solution: Cyclemania 0.08.44: See Source Code tab for recent change history.Dawf: Dual Audio Workflow: Beta 2: Fix little bugs and improve usablity by changing the way it finds the good audio.DotNetNuke Referral Tracker: 2.0.1: First releaseFoursquare for Windows Phone 7: Foursquare 2010.03.29.02: Foursquare 2010.03.29.02GEGetDocConfig: GEGETDOCCONFIG.ZIP: Installation: Simply download the zip file and extract the executable into its own directory on the SharePoint front end server Note: There will b...GKO Libraries: GKO Libraries 0.2 Beta: Added: Binary search Unmanaged wrappers, interop and pinvoke functions and structures Windows service wrapper Video mode helpers and more.....Google Maps API for .NET: GoogleMapsForNET v0.9 alpha release: First version, contains Core library featuring: Geocoding API Elevation API Static Maps APIGoogle Maps API for .NET: GoogleMapsForNET v0.9.1 alpha release: Fixed dependencies issues; added NUnit binaries and updated Newtonsoft Json library.Google Maps API for .NET: GoogleMapsForNET v0.9.2a alpha release: Recommended update.Code clean-up; did refactoring and major interface changes in Static Maps because it wasn't aligned to the 'simplest and least r...Home Access Plus+: v3.2.0.0: v3.2.0.0 Release Change Log: More AJAX to reduce page refreshes (Deleting, New Folder, Rename moved from browser popups) Only 3 Browser Popups (1...Html to OpenXml: HtmlToOpenXml 1.1: The dll library to include in your project. The dll is signed for GAC support. Compiled with .Net 3.5, Dependencies on System.Drawing.dll and Docu...Latent Semantic Analysis: Latest sources: Just the latest sources. Just click the changeset. Please note that in order to compile this code you need to download some additional code. You ...Load Test User Mock Toolkits: Load Test User Mock Toolkits Help Doc: Samples and The framework introduction. 包括框架介绍和典型示例Load Test User Mock Toolkits: Open.LoadTest.User.Mock.Toolkits 1.0 alpha: 此版本为非正式版本，未对性能方面进行优化。而且框架正在重构调整中。Mobile Broadband Logging Monitor: Mobile Broadband Logging Monitor 1.2.4: This edition supports: Newer and older editions of Birdstep Technology's EasyConnect HUAWEI Mobile Partner MWConn User defined location for s...Nito.KitchenSink: Version 3: Added Encoding.GetString(Stream, bool) for converting an entire stream into a string. Changed Stream.CopyTo to allow the stream to be closed/abor...Numina Application Framework: Numina.Framework Core 49088: Fixed Bug with Headers introduced in rev. 48249 with change to HttpUtil class. admin/User_Pending.aspx page users weren't able to be deleted Do...OAuthLib: OAuthLib (1.6.4.0): Fix for 6390 Make it possible to configure time out value.Quack Quack Says the Duck: Quack Quack Says The Duck 1.1.0.0: This new release pushes some work onto a background thread clearing issues with multiple screen clicks while the UI was blocking.Rapidshare Episode Downloader: RED v0.8.4: - Added Edit feature - Moved season & episode int to string into a separate function - Fixed some more minor issues - Added 'Previous' feature - F...RoTwee: RoTwee (8.1.3.0): Update OAuthLib to 1.6.4.0SharePoint Company Directory / Active Directory Self Service System: SharePoint Company Directory with AD Import: This is a very simple system which was designed for a Bank to allow users to update their contact information within SharePoint . Then this info ca...Simply Classified: v1.00.12: Comsite Simply Classified v1.00.12 - STABLE - Tested against DotNetNuke v4.9.5 and v5.2.x Bug Fixes/Enhancements: BUGFIX: Resolved issues with 1...sPATCH: sPatch v0.9: Completely Recoded with wxWidgetsFollowing Content is different to .NET Patcher no requirement for .NET Framework Manual patch was removed to av...SSAS Profiler Trace Scheduler: SSAS Profiler Trace Scheduler: AS Profiler Scheduler is a tool that will enable Scheduling of SQL AS Tracing using predefined Profiler Templates. For tracking different issues th...sysFix: sysfix build v5: A stable beta release, please refer to home page for further details.VOB2MKV: vob2mkv-1.0.4: This is a feature update of the VOB2MKV utility. The command-line parsing in the VOB2MKV application has been greatly improved. You can now get f...xnaWebcam: xnaWebcam 0.1: xnaWebcam 0.1 Program Version 0.1: -Show Webcam Device -Draw.String WebcamTexture.VideoDevice.Name.ToString() Instructions: 1. Plug-in your Webca...xnaWebcam: xnaWebcam 0.2: xnaWebcam 0.2 Version 0.2: -setResolution -Keys.Escape: this.Exit() << Exit the Game/Application. --- Version 0.1: -Show Webcam Device -Draw.Strin...xnaWebcam: xnaWebcam 0.21: xnaWebcam 0.2 Version 0.21: -Fix: Don't quit game/application after closing mainGameWindow -Fix: Text Position; Window.X, Window.Y --- Version 0.2...Xploit Game Engine: Xploit_1_1 Release: Added Features Multiple Mesh instancing.Xploit Game Engine: Xploit_1_1 Source Code: Updates Create multiple instances of the same Meshe using XModelMesh and XSkinnedMesh.Yakiimo3D: DX11 DirectCompute Buddhabrot Source and Binary: DX11 DirectCompute Buddhabrot/Nebulabrot source and binary.Most Popular ProjectsRawrWBFS ManagerASP.NET Ajax LibraryMicrosoft SQL Server Product Samples: DatabaseSilverlight ToolkitAJAX Control ToolkitWindows Presentation Foundation (WPF)LiveUpload to FacebookASP.NETMicrosoft SQL Server Community & SamplesMost Active ProjectsRawrjQuery Library for SharePoint Web ServicesBlogEngine.NETLINQ to TwitterManaged Extensibility FrameworkMicrosoft Biology FoundationFarseer Physics EngineN2 CMSNB_Store - Free DotNetNuke Ecommerce Catalog Modulepatterns & practices – Enterprise Library

  Read the article

• How to Use USER_DEFINED Activity in OWB Process Flow

  - by Jinggen He

  Process Flow is a very important component of Oracle Warehouse Builder. With Process Flow, we can create and control the ETL process by setting all kinds of activities in a well-constructed flow. In Oracle Warehouse Builder 11gR2, there are 28 kinds of activities, which fall into three categories: Control activities, OWB specific activities and Utility activities. For more information about Process Flow activities, please refer to OWB online doc. Most of those activities are pre-defined for some specific use. For example, the Mapping activity allows execution an OWB mapping in Process Flow and the FTP activity allows an interaction between the local host and a remote FTP server. Besides those activities for specific purposes, the User Defined activity enables you to incorporate into a Process Flow an activity that is not defined within Warehouse Builder. So the User Defined activity brings flexibility and extensibility to Process Flow. In this article, we will take an amazing tour of using the User Defined activity. Let's start. Enable execution of User Defined activity Let's start this section from creating a very simple Process Flow, which contains a Start activity, a User Defined activity and an End Success activity. Leave all parameters of activity USER_DEFINED unchanged except that we enter /tmp/test.sh into the Value column of the COMMAND parameter. Then let's create the shell script test.sh in /tmp directory. Here is the content of /tmp/test.sh (this article is demonstrating a scenario in Linux system, and /tmp/test.sh is a Bash shell script): echo Hello World! > /tmp/test.txt Note: don't forget to grant the execution privilege on /tmp/test.sh to OS Oracle user. For simplicity, we just use the following command. chmod +x /tmp/test.sh OK, it's so simple that we’ve almost done it. Now deploy the Process Flow and run it. For a newly installed OWB, we will come across an error saying "RPE-02248: For security reasons, activity operator Shell has been disabled by the DBA". See below. That's because, by default, the User Defined activity is DISABLED. Configuration about this can be found in <ORACLE_HOME>/owb/bin/admin/Runtime.properties: property.RuntimePlatform.0.NativeExecution.Shell.security_constraint=DISABLED The property can be set to three different values: NATIVE_JAVA, SCHEDULER and DISBALED. Where NATIVE_JAVA uses the Java 'Runtime.exec' interface, SCHEDULER uses a DBMS Scheduler external job submitted by the Control Center repository owner which is executed by the default operating system user configured by the DBA. DISABLED prevents execution via these operators. We enable the execution of User Defined activity by setting: property.RuntimePlatform.0.NativeExecution.Shell.security_constraint= NATIVE_JAVA Restart the Control Center service for the change of setting to take effect. cd <ORACLE_HOME>/owb/rtp/sql sqlplus OWBSYS/<password of OWBSYS> @stop_service.sql sqlplus OWBSYS/<password of OWBSYS> @start_service.sql And then run the Process Flow again. We will see that the Process Flow completes successfully. The execution of /tmp/test.sh successfully generated a file /tmp/test.txt, containing the line Hello World!. Pass parameters to User Defined Activity The Process Flow created in the above section has a drawback: the User Defined activity doesn't accept any information from OWB nor does it give any meaningful results back to OWB. That's to say, it lacks interaction. Maybe, sometimes such a Process Flow can fulfill the business requirement. But for most of the time, we need to get the User Defined activity executed according to some information prior to that step. In this section, we will see how to pass parameters to the User Defined activity and pass them into the to-be-executed shell script. First, let's see how to pass parameters to the script. The User Defined activity has an input parameter named PARAMETER_LIST. This is a list of parameters that will be passed to the command. Parameters are separated from one another by a token. The token is taken as the first character on the PARAMETER_LIST string, and the string must also end in that token. Warehouse Builder recommends the '?' character, but any character can be used. For example, to pass 'abc,' 'def,' and 'ghi' you can use the following equivalent: ?abc?def?ghi? or !abc!def!ghi! or |abc|def|ghi| If the token character or '\' needs to be included as part of the parameter, then it must be preceded with '\'. For example '\\'. If '\' is the token character, then '/' becomes the escape character. Let's configure the PARAMETER_LIST parameter as below: And modify the shell script /tmp/test.sh as below: echo $1 is saying hello to $2! > /tmp/test.txt Re-deploy the Process Flow and run it. We will see that the generated /tmp/test.txt contains the following line: Bob is saying hello to Alice! In the example above, the parameters passed into the shell script are static. This case is not so useful because: instead of passing parameters, we can directly write the value of the parameters in the shell script. To make the case more meaningful, we can pass two dynamic parameters, that are obtained from the previous activity, to the shell script. Prepare the Process Flow as below: The Mapping activity MAPPING_1 has two output parameters: FROM_USER, TO_USER. The User Defined activity has two input parameters: FROM_USER, TO_USER. All the four parameters are of String type. Additionally, the Process Flow has two string variables: VARIABLE_FOR_FROM_USER, VARIABLE_FOR_TO_USER. Through VARIABLE_FOR_FROM_USER, the input parameter FROM_USER of USER_DEFINED gets value from output parameter FROM_USER of MAPPING_1. We achieve this by binding both parameters to VARIABLE_FOR_FROM_USER. See the two figures below. In the same way, through VARIABLE_FOR_TO_USER, the input parameter TO_USER of USER_DEFINED gets value from output parameter TO_USER of MAPPING_1. Also, we need to change the PARAMETER_LIST of the User Defined activity like below: Now, the shell script is getting input from the Mapping activity dynamically. Deploy the Process Flow and all of its necessary dependees then run the Process Flow. We see that the generated /tmp/test.txt contains the following line: USER B is saying hello to USER A! 'USER B' and 'USER A' are two outputs of the Mapping execution. Write the shell script within Oracle Warehouse Builder In the previous section, the shell script is located in the /tmp directory. But sometimes, when the shell script is small, or for the sake of maintaining consistency, you may want to keep the shell script inside Oracle Warehouse Builder. We can achieve this by configuring these three parameters of a User Defined activity properly: COMMAND: Set the path of interpreter, by which the shell script will be interpreted. PARAMETER_LIST: Set it blank. SCRIPT: Enter the shell script content. Note that in Linux the shell script content is passed into the interpreter as standard input at runtime. About how to actually pass parameters to the shell script, we can utilize variable substitutions. As in the following figure, ${FROM_USER} will be replaced by the value of the FROM_USER input parameter of the User Defined activity. So will the ${TO_USER} symbol. Besides the custom substitution variables, OWB also provide some system pre-defined substitution variables. You can refer to the online document for that. Deploy the Process Flow and run it. We see that the generated /tmp/test.txt contains the following line: USER B is saying hello to USER A! Leverage the return value of User Defined activity All of the previous sections are connecting the User Defined activity to END_SUCCESS with an unconditional transition. But what should we do if we want different subsequent activities for different shell script execution results? 1.  The simplest way is to add three simple-conditioned out-going transitions for the User Defined activity just like the figure below. In the figure, to simplify the scenario, we connect the User Defined activity to three End activities. Basically, if the shell script ends successfully, the whole Process Flow will end at END_SUCCESS, otherwise, the whole Process Flow will end at END_ERROR (in our case, ending at END_WARNING seldom happens). In the real world, we can add more complex and meaningful subsequent business logic. 2.  Or we can utilize complex conditions to work with different results of the User Defined activity. Previously, in our script, we only have this line: echo ${FROM_USER} is saying hello to ${TO_USER}! > /tmp/test.txt We can add more logic in it and return different values accordingly. echo ${FROM_USER} is saying hello to ${TO_USER}! > /tmp/test.txt if CONDITION_1 ; then ...... exit 0 fi if CONDITION_2 ; then ...... exit 2 fi if CONDITION_3 ; then ...... exit 3 fi After that we can leverage the result by checking RESULT_CODE in condition expression of those out-going transitions. Let's suppose that we have the Process Flow as the following graph (SUB_PROCESS_n stands for more different further processes): We can set complex condition for the transition from USER_DEFINED to SUB_PROCESS_1 like this: Other transitions can be set in the same way. Note that, in our shell script, we return 0, 2 and 3, but not 1. As in Linux system, if the shell script comes across a system error like IO error, the return value will be 1. We can explicitly handle such a return value. Summary Let's summarize what has been discussed in this article: How to create a Process Flow with a User Defined activity in it How to pass parameters from the prior activity to the User Defined activity and finally into the shell script How to write the shell script within Oracle Warehouse Builder How to do variable substitutions How to let the User Defined activity return different values and in what way can we leverage

  Read the article

• Simple Branching and Merging with SVN

  Its a good idea not to do too much work without checking something into source control.  By too much work I mean typically on the order of a couple of hours at most, and certainly its a good practice to check in anything you have before you leave the office for the day.  But what if your changes break the build (on the build server you do have a build server dont you?) or would cause problems for others on your team if they get the latest code?  The solution with Subversion is branching and merging (incidentally, if youre using Microsoft Visual Studio Team System, you can shelve your changes and share shelvesets with others, which accomplishes many of the same things as branching and merging, but is a bit simpler to do). Getting Started Im going to assume you have Subversion installed along with the nearly ubiquitous client, TortoiseSVN.  See my previous post on installing SVN server if you want to get it set up real quick (you can put it on your workstation/laptop just to learn how it works easily enough). Overview When you know you are going to be working on something that you wont be able to check in quickly, its a good idea to start a branch.  Its also perfectly fine to create the branch after-the-fact (have you ever started something thinking it would be an hour and 4 hours later realized you were nowhere near done?).  In any event, the first thing you need to do is create a branch.  A branch is simply a copy of the current trunk (a typical subversion setup has root directories called trunk, tags, and branches its a good idea to keep this and to put your branches in the branches folder).  Once you have a new branch, you need to switch your working copy so that it is bound to your branch.  As you work,  you may want to merge in changes that are happening in the trunk to your branch, and ultimately when you are done youll want to merge your branch back into the trunk.  When done, you can delete your branch (or not, but it may add clutter).  To sum up: Create a new branch Switch your local working copy to the new branch Develop in the branch (commit changes, etc.) Merge changes from trunk into your branch Merge changes from branch into trunk Delete the branch Create a new branch From the root of your repository, right-click and select TortoiseSVN > Branch/tag as shown at right (click to enlarge).  This will bring up the Copy (Branch / Tag) interface.  By default the From WC at URL: should be pointing at the trunk of your repository.  I recommend (after ensuring that you have the latest version) that you choose to make the copy from the HEAD revision in the repository (the first radio button).  In the To URL: textbox, you should change the URL from /trunk to /branches/NAME_OF_BRANCH.  You can name the branch anything you like, but its often useful to give it your name (if its just for your use) or some useful information (such as a datestamp or a bug/issue ID from that it relates to, or perhaps just the name of the feature you are adding. When youre done with that, enter in a log message for your new branch.  If you want to immediately switch your local working copy to the new branch/tag, check the box at the bottom of the dialog (Switch working copy to new branch/tag).  You can see an example at right. Assuming everything works, you should very quickly see a window telling you the Copy finished, like the one shown below: Switch Local Working Copy to New Branch If you followed the instructions above and checked the box when you created your branch, you dont need to do this step.  However, if you have a branch that already exists and you would like to switch over to working on it, you can do so by using the Switch command.  Youll find it in the explorer context menu under TortoiseSVN > Switch: This brings up a dialog that shows you your current binding, and lets you enter in a new URL to switch to: In the screenshot above, you can see that Im currently bound to a branch, and so I could switch back to the trunk or to another branch.  If youre not sure what to enter here, you can click the [] next to the URL textbox to explore your repository and find the appropriate root URL to use.  Also, the dropdown will show you URLs that might be a good fit (such as the trunk of the current repository). Develop in the Branch Once you have created a branch and switched your working copy to use it,  you can make changes and Commit them as usual.  Your commits are now going into the branch, so they wont impact other users or the build server that are working off of the trunk (or their own branches).  In theory you can keep on doing this forever, but practically its a good idea to periodically merge the trunk into your branch, and/or keep your branches short-lived and merge them back into the trunk before they get too far out of sync. Merge Changes from Trunk into your Branch Once you have been working in a branch for a little while, change to the trunk will have occurred that youll want to merge into your branch.  Its much safer and easier to integrate changes in small increments than to wait for weeks or months and then try to merge in two very different codebases.  To perform the merge, simply go to the root of your branch working copy and right click, select TortoiseSVN->Merge.  Youll be presented with this dialog: In this case you want to leave the default setting, Merge a range of revisions.  Click Next.  Now choose the URL to merge from.  You should select the trunk of your current repository (which should be in the dropdownlist, or you can click the [] to browse your repository for the correct URL).  You can leave everything else blank since you want to merge everything: Click Next.  Again you can leave the default settings.  If you want to do something more granular than everything in the trunk, you can select a different Merge depth, to include merging just one item in the tree.  You can also perform a Test merge to see what changes will take place before you click Merge (which is often a good idea).  Heres what the dialog should look like before you click Merge: After clicking Merge (or Test merge) you should see a confirmation like this (it will say Test Only in the title if you click Test merge): Now you should build your solution, run all of your tests, and verify that your branch still works the way it should, given the updates that youve just integrated from the trunk.  Once everything works, Commit your changes, and then continue with your work on the branch.  Note that until you commit, nothing has actually changed in your branch on the server.  Other team members who may also be working in this branch wont be impacted, etc.  The Merge is purely a client-side operation until you perform a Commit. In a more real-world scenario, you may have conflicts.  When you do, youll be presented with a dialog like this one: Its up to you which option you want to go with.  The more frequently you Merge, the fewer of these youll have to deal with.  Also, be very sure that youre merging the right folders together.  If you try and merge your trunk with some subfolder in your branchs structure, youll end up with all kinds of conflicts and problems.  Fortunately, theyre only on your working copy (unless you commit them!) but if you see something like that, be sure to doublecheck your URL and your local file location. Merge Your Branch Back Into Trunk When youre done working in your branch, its time to pull it back into the trunk.  The first thing you should do is follow the previous steps instructions for merging the latest from the trunk into your branch.  This lets you ensure that what you have in your branch works correctly with the current trunk.  Once youve done that and committed your changes to your branch, youre ready to proceed with this step. Once youre confident your branch is good to go, you should go to its root folder and select TortoiseSVN->Merge (as above) from the explorer right-click menu.  This time, select Reintegrate a branch as shown below: Click Next.  Youll want it to merge with the trunk, which should be the default: Click Next. Leave the default settings: Click Test merge to see a test, and then if all looks good, click Merge.  Note that if you havent checked in your working copy changes, youll see something like this: If on the other hand things are successful: After this step, its likely you are finished working in your branch.  Dont forget to use the ToroiseSVN->Switch command to change your working copy back to the trunk. Delete the Branch You dont have to delete the branch, but over time your branches area of your repository will get cluttered, and in any event if theyre not actively being worked on the branches are just taking up space and adding to later confusion.  Keeping your branches limited to things youre actively working on is simply a good habit to get into, just like making sure your codebase itself remains tidy and not filled with old commented out bits of code. To delete the branch after youre finished with it, the simplest thing to do is choose TortoiseSVN->Repo Browser.  From there, assuming you did this from your branch, it should already be highlighted.  In any event, navigate to your branch in the treeview on the left, and then right-click and select Delete.  Enter a log message if youd like: Click OK, and its gone.  Dont be too afraid of this, though.  You can still get to the files by viewing the log for branches, and selecting a previous revision (anything before the delete action): If for some reason you needed something that was previously in this branch, you could easily get back to any changeset you checked in, so you should have absolutely no fear when it comes to deleting branches youre done with.   Resources If youre using Eclipse, theres a nice write-up of the steps required by Zach Cox that I found helpful here. Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

  Read the article

• Creating a Dynamic DataRow for easier DataRow Syntax

  - by Rick Strahl

  I've been thrown back into an older project that uses DataSets and DataRows as their entity storage model. I have several applications internally that I still maintain that run just fine (and I sometimes wonder if this wasn't easier than all this ORM crap we deal with with 'newer' improved technology today - but I disgress) but use this older code. For the most part DataSets/DataTables/DataRows are abstracted away in a pseudo entity model, but in some situations like queries DataTables and DataRows are still surfaced to the business layer. Here's an example. Here's a business object method that runs dynamic query and the code ends up looping over the result set using the ugly DataRow Array syntax:public int UpdateAllSafeTitles() { int result = this.Execute("select pk, title, safetitle from " + Tablename + " where EntryType=1", "TPks"); if (result < 0) return result; result = 0; foreach (DataRow row in this.DataSet.Tables["TPks"].Rows) { string title = row["title"] as string; string safeTitle = row["safeTitle"] as string; int pk = (int)row["pk"]; string newSafeTitle = this.GetSafeTitle(title); if (newSafeTitle != safeTitle) { this.ExecuteNonQuery("update " + this.Tablename + " set safeTitle=@safeTitle where pk=@pk", this.CreateParameter("@safeTitle",newSafeTitle), this.CreateParameter("@pk",pk) ); result++; } } return result; } The problem with looping over DataRow objecs is two fold: The array syntax is tedious to type and not real clear to look at, and explicit casting is required in order to do anything useful with the values. I've highlighted the place where this matters. Using the DynamicDataRow class I'll show in a minute this code can be changed to look like this:public int UpdateAllSafeTitles() { int result = this.Execute("select pk, title, safetitle from " + Tablename + " where EntryType=1", "TPks"); if (result < 0) return result; result = 0; foreach (DataRow row in this.DataSet.Tables["TPks"].Rows) { dynamic entry = new DynamicDataRow(row); string newSafeTitle = this.GetSafeTitle(entry.title); if (newSafeTitle != entry.safeTitle) { this.ExecuteNonQuery("update " + this.Tablename + " set safeTitle=@safeTitle where pk=@pk", this.CreateParameter("@safeTitle",newSafeTitle), this.CreateParameter("@pk",entry.pk) ); result++; } } return result; } The code looks much a bit more natural and describes what's happening a little nicer as well. Well, using the new dynamic features in .NET it's actually quite easy to implement the DynamicDataRow class. Creating your own custom Dynamic Objects .NET 4.0 introduced the Dynamic Language Runtime (DLR) and opened up a whole bunch of new capabilities for .NET applications. The dynamic type is an easy way to avoid Reflection and directly access members of 'dynamic' or 'late bound' objects at runtime. There's a lot of very subtle but extremely useful stuff that dynamic does (especially for COM Interop scenearios) but in its simplest form it often allows you to do away with manual Reflection at runtime. In addition you can create DynamicObject implementations that can perform  custom interception of member accesses and so allow you to provide more natural access to more complex or awkward data structures like the DataRow that I use as an example here. Bascially you can subclass DynamicObject and then implement a few methods (TryGetMember, TrySetMember, TryInvokeMember) to provide the ability to return dynamic results from just about any data structure using simple property/method access. In the code above, I created a custom DynamicDataRow class which inherits from DynamicObject and implements only TryGetMember and TrySetMember. Here's what simple class looks like:/// <summary> /// This class provides an easy way to turn a DataRow /// into a Dynamic object that supports direct property /// access to the DataRow fields. /// /// The class also automatically fixes up DbNull values /// (null into .NET and DbNUll to DataRow) /// </summary> public class DynamicDataRow : DynamicObject { /// <summary> /// Instance of object passed in /// </summary> DataRow DataRow; /// <summary> /// Pass in a DataRow to work off /// </summary> /// <param name="instance"></param> public DynamicDataRow(DataRow dataRow) { DataRow = dataRow; } /// <summary> /// Returns a value from a DataRow items array. /// If the field doesn't exist null is returned. /// DbNull values are turned into .NET nulls. /// /// </summary> /// <param name="binder"></param> /// <param name="result"></param> /// <returns></returns> public override bool TryGetMember(GetMemberBinder binder, out object result) { result = null; try { result = DataRow[binder.Name]; if (result == DBNull.Value) result = null; return true; } catch { } result = null; return false; } /// <summary> /// Property setter implementation tries to retrieve value from instance /// first then into this object /// </summary> /// <param name="binder"></param> /// <param name="value"></param> /// <returns></returns> public override bool TrySetMember(SetMemberBinder binder, object value) { try { if (value == null) value = DBNull.Value; DataRow[binder.Name] = value; return true; } catch {} return false; } } To demonstrate the basic features here's a short test: [TestMethod] [ExpectedException(typeof(RuntimeBinderException))] public void BasicDataRowTests() { DataTable table = new DataTable("table"); table.Columns.Add( new DataColumn() { ColumnName = "Name", DataType=typeof(string) }); table.Columns.Add( new DataColumn() { ColumnName = "Entered", DataType=typeof(DateTime) }); table.Columns.Add(new DataColumn() { ColumnName = "NullValue", DataType = typeof(string) }); DataRow row = table.NewRow(); DateTime now = DateTime.Now; row["Name"] = "Rick"; row["Entered"] = now; row["NullValue"] = null; // converted in DbNull dynamic drow = new DynamicDataRow(row); string name = drow.Name; DateTime entered = drow.Entered; string nulled = drow.NullValue; Assert.AreEqual(name, "Rick"); Assert.AreEqual(entered,now); Assert.IsNull(nulled); // this should throw a RuntimeBinderException Assert.AreEqual(entered,drow.enteredd); } The DynamicDataRow requires a custom constructor that accepts a single parameter that sets the DataRow. Once that's done you can access property values that match the field names. Note that types are automatically converted - no type casting is needed in the code you write. The class also automatically converts DbNulls to regular nulls and vice versa which is something that makes it much easier to deal with data returned from a database. What's cool here isn't so much the functionality - even if I'd prefer to leave DataRow behind ASAP -  but the fact that we can create a dynamic type that uses a DataRow as it's 'DataSource' to serve member values. It's pretty useful feature if you think about it, especially given how little code it takes to implement. By implementing these two simple methods we get to provide two features I was complaining about at the beginning that are missing from the DataRow: Direct Property Syntax Automatic Type Casting so no explicit casts are required Caveats As cool and easy as this functionality is, it's important to understand that it doesn't come for free. The dynamic features in .NET are - well - dynamic. Which means they are essentially evaluated at runtime (late bound). Rather than static typing where everything is compiled and linked by the compiler/linker, member invokations are looked up at runtime and essentially call into your custom code. There's some overhead in this. Direct invocations - the original code I showed - is going to be faster than the equivalent dynamic code. However, in the above code the difference of running the dynamic code and the original data access code was very minor. The loop running over 1500 result records took on average 13ms with the original code and 14ms with the dynamic code. Not exactly a serious performance bottleneck. One thing to remember is that Microsoft optimized the DLR code significantly so that repeated calls to the same operations are routed very efficiently which actually makes for very fast evaluation. The bottom line for performance with dynamic code is: Make sure you test and profile your code if you think that there might be a performance issue. However, in my experience with dynamic types so far performance is pretty good for repeated operations (ie. in loops). While usually a little slower the perf hit is a lot less typically than equivalent Reflection work. Although the code in the second example looks like standard object syntax, dynamic is not static code. It's evaluated at runtime and so there's no type recognition until runtime. This means no Intellisense at development time, and any invalid references that call into 'properties' (ie. fields in the DataRow) that don't exist still cause runtime errors. So in the case of the data row you still get a runtime error if you mistype a column name:// this should throw a RuntimeBinderException Assert.AreEqual(entered,drow.enteredd); Dynamic - Lots of uses The arrival of Dynamic types in .NET has been met with mixed emotions. Die hard .NET developers decry dynamic types as an abomination to the language. After all what dynamic accomplishes goes against all that a static language is supposed to provide. On the other hand there are clearly scenarios when dynamic can make life much easier (COM Interop being one place). Think of the possibilities. What other data structures would you like to expose to a simple property interface rather than some sort of collection or dictionary? And beyond what I showed here you can also implement 'Method missing' behavior on objects with InvokeMember which essentially allows you to create dynamic methods. It's all very flexible and maybe just as important: It's easy to do. There's a lot of power hidden in this seemingly simple interface. Your move…© Rick Strahl, West Wind Technologies, 2005-2011Posted in CSharp  .NET   Tweet (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

  Read the article

• So…is it a Seek or a Scan?

  - by Paul White

  You’re probably most familiar with the terms ‘Seek’ and ‘Scan’ from the graphical plans produced by SQL Server Management Studio (SSMS).  The image to the left shows the most common ones, with the three types of scan at the top, followed by four types of seek.  You might look to the SSMS tool-tip descriptions to explain the differences between them: Not hugely helpful are they?  Both mention scans and ranges (nothing about seeks) and the Index Seek description implies that it will not scan the index entirely (which isn’t necessarily true). Recall also yesterday’s post where we saw two Clustered Index Seek operations doing very different things.  The first Seek performed 63 single-row seeking operations; and the second performed a ‘Range Scan’ (more on those later in this post).  I hope you agree that those were two very different operations, and perhaps you are wondering why there aren’t different graphical plan icons for Range Scans and Seeks?  I have often wondered about that, and the first person to mention it after yesterday’s post was Erin Stellato (twitter | blog): Before we go on to make sense of all this, let’s look at another example of how SQL Server confusingly mixes the terms ‘Scan’ and ‘Seek’ in different contexts.  The diagram below shows a very simple heap table with two columns, one of which is the non-clustered Primary Key, and the other has a non-unique non-clustered index defined on it.  The right hand side of the diagram shows a simple query, it’s associated query plan, and a couple of extracts from the SSMS tool-tip and Properties windows. Notice the ‘scan direction’ entry in the Properties window snippet.  Is this a seek or a scan?  The different references to Scans and Seeks are even more pronounced in the XML plan output that the graphical plan is based on.  This fragment is what lies behind the single Index Seek icon shown above: You’ll find the same confusing references to Seeks and Scans throughout the product and its documentation. Making Sense of Seeks Let’s forget all about scans for a moment, and think purely about seeks.  Loosely speaking, a seek is the process of navigating an index B-tree to find a particular index record, most often at the leaf level.  A seek starts at the root and navigates down through the levels of the index to find the point of interest: Singleton Lookups The simplest sort of seek predicate performs this traversal to find (at most) a single record.  This is the case when we search for a single value using a unique index and an equality predicate.  It should be readily apparent that this type of search will either find one record, or none at all.  This operation is known as a singleton lookup.  Given the example table from before, the following query is an example of a singleton lookup seek: Sadly, there’s nothing in the graphical plan or XML output to show that this is a singleton lookup – you have to infer it from the fact that this is a single-value equality seek on a unique index.  The other common examples of a singleton lookup are bookmark lookups – both the RID and Key Lookup forms are singleton lookups (an RID lookup finds a single record in a heap from the unique row locator, and a Key Lookup does much the same thing on a clustered table).  If you happen to run your query with STATISTICS IO ON, you will notice that ‘Scan Count’ is always zero for a singleton lookup. Range Scans The other type of seek predicate is a ‘seek plus range scan’, which I will refer to simply as a range scan.  The seek operation makes an initial descent into the index structure to find the first leaf row that qualifies, and then performs a range scan (either backwards or forwards in the index) until it reaches the end of the scan range. The ability of a range scan to proceed in either direction comes about because index pages at the same level are connected by a doubly-linked list – each page has a pointer to the previous page (in logical key order) as well as a pointer to the following page.  The doubly-linked list is represented by the green and red dotted arrows in the index diagram presented earlier.  One subtle (but important) point is that the notion of a ‘forward’ or ‘backward’ scan applies to the logical key order defined when the index was built.  In the present case, the non-clustered primary key index was created as follows: CREATE TABLE dbo.Example ( key_col INTEGER NOT NULL, data INTEGER NOT NULL, CONSTRAINT [PK dbo.Example key_col] PRIMARY KEY NONCLUSTERED (key_col ASC) ) ; Notice that the primary key index specifies an ascending sort order for the single key column.  This means that a forward scan of the index will retrieve keys in ascending order, while a backward scan would retrieve keys in descending key order.  If the index had been created instead on key_col DESC, a forward scan would retrieve keys in descending order, and a backward scan would return keys in ascending order. A range scan seek predicate may have a Start condition, an End condition, or both.  Where one is missing, the scan starts (or ends) at one extreme end of the index, depending on the scan direction.  Some examples might help clarify that: the following diagram shows four queries, each of which performs a single seek against a column holding every integer from 1 to 100 inclusive.  The results from each query are shown in the blue columns, and relevant attributes from the Properties window appear on the right: Query 1 specifies that all key_col values less than 5 should be returned in ascending order.  The query plan achieves this by seeking to the start of the index leaf (there is no explicit starting value) and scanning forward until the End condition (key_col < 5) is no longer satisfied (SQL Server knows it can stop looking as soon as it finds a key_col value that isn’t less than 5 because all later index entries are guaranteed to sort higher). Query 2 asks for key_col values greater than 95, in descending order.  SQL Server returns these results by seeking to the end of the index, and scanning backwards (in descending key order) until it comes across a row that isn’t greater than 95.  Sharp-eyed readers may notice that the end-of-scan condition is shown as a Start range value.  This is a bug in the XML show plan which bubbles up to the Properties window – when a backward scan is performed, the roles of the Start and End values are reversed, but the plan does not reflect that.  Oh well. Query 3 looks for key_col values that are greater than or equal to 10, and less than 15, in ascending order.  This time, SQL Server seeks to the first index record that matches the Start condition (key_col >= 10) and then scans forward through the leaf pages until the End condition (key_col < 15) is no longer met. Query 4 performs much the same sort of operation as Query 3, but requests the output in descending order.  Again, we have to mentally reverse the Start and End conditions because of the bug, but otherwise the process is the same as always: SQL Server finds the highest-sorting record that meets the condition ‘key_col < 25’ and scans backward until ‘key_col >= 20’ is no longer true. One final point to note: seek operations always have the Ordered: True attribute.  This means that the operator always produces rows in a sorted order, either ascending or descending depending on how the index was defined, and whether the scan part of the operation is forward or backward.  You cannot rely on this sort order in your queries of course (you must always specify an ORDER BY clause if order is important) but SQL Server can make use of the sort order internally.  In the four queries above, the query optimizer was able to avoid an explicit Sort operator to honour the ORDER BY clause, for example. Multiple Seek Predicates As we saw yesterday, a single index seek plan operator can contain one or more seek predicates.  These seek predicates can either be all singleton seeks or all range scans – SQL Server does not mix them.  For example, you might expect the following query to contain two seek predicates, a singleton seek to find the single record in the unique index where key_col = 10, and a range scan to find the key_col values between 15 and 20: SELECT key_col FROM dbo.Example WHERE key_col = 10 OR key_col BETWEEN 15 AND 20 ORDER BY key_col ASC ; In fact, SQL Server transforms the singleton seek (key_col = 10) to the equivalent range scan, Start:[key_col >= 10], End:[key_col <= 10].  This allows both range scans to be evaluated by a single seek operator.  To be clear, this query results in two range scans: one from 10 to 10, and one from 15 to 20. Final Thoughts That’s it for today – tomorrow we’ll look at monitoring singleton lookups and range scans, and I’ll show you a seek on a heap table. Yes, a seek.  On a heap.  Not an index! If you would like to run the queries in this post for yourself, there’s a script below.  Thanks for reading! IF OBJECT_ID(N'dbo.Example', N'U') IS NOT NULL BEGIN DROP TABLE dbo.Example; END ; -- Test table is a heap -- Non-clustered primary key on 'key_col' CREATE TABLE dbo.Example ( key_col INTEGER NOT NULL, data INTEGER NOT NULL, CONSTRAINT [PK dbo.Example key_col] PRIMARY KEY NONCLUSTERED (key_col) ) ; -- Non-unique non-clustered index on the 'data' column CREATE NONCLUSTERED INDEX [IX dbo.Example data] ON dbo.Example (data) ; -- Add 100 rows INSERT dbo.Example WITH (TABLOCKX) ( key_col, data ) SELECT key_col = V.number, data = V.number FROM master.dbo.spt_values AS V WHERE V.[type] = N'P' AND V.number BETWEEN 1 AND 100 ; -- ================ -- Singleton lookup -- ================ ; -- Single value equality seek in a unique index -- Scan count = 0 when STATISTIS IO is ON -- Check the XML SHOWPLAN SELECT E.key_col FROM dbo.Example AS E WHERE E.key_col = 32 ; -- =========== -- Range Scans -- =========== ; -- Query 1 SELECT E.key_col FROM dbo.Example AS E WHERE E.key_col <= 5 ORDER BY E.key_col ASC ; -- Query 2 SELECT E.key_col FROM dbo.Example AS E WHERE E.key_col > 95 ORDER BY E.key_col DESC ; -- Query 3 SELECT E.key_col FROM dbo.Example AS E WHERE E.key_col >= 10 AND E.key_col < 15 ORDER BY E.key_col ASC ; -- Query 4 SELECT E.key_col FROM dbo.Example AS E WHERE E.key_col >= 20 AND E.key_col < 25 ORDER BY E.key_col DESC ; -- Final query (singleton + range = 2 range scans) SELECT E.key_col FROM dbo.Example AS E WHERE E.key_col = 10 OR E.key_col BETWEEN 15 AND 20 ORDER BY E.key_col ASC ; -- === TIDY UP === DROP TABLE dbo.Example; © 2011 Paul White email: [email protected] twitter: @SQL_Kiwi

  Read the article

• C#: String Concatenation vs Format vs StringBuilder

  - by James Michael Hare

  I was looking through my groups’ C# coding standards the other day and there were a couple of legacy items in there that caught my eye.  They had been passed down from committee to committee so many times that no one even thought to second guess and try them for a long time.  It’s yet another example of how micro-optimizations can often get the best of us and cause us to write code that is not as maintainable as it could be for the sake of squeezing an extra ounce of performance out of our software. So the two standards in question were these, in paraphrase: Prefer StringBuilder or string.Format() to string concatenation. Prefer string.Equals() with case-insensitive option to string.ToUpper().Equals(). Now some of you may already know what my results are going to show, as these items have been compared before on many blogs, but I think it’s always worth repeating and trying these yourself.  So let’s dig in. The first test was a pretty standard one.  When concattenating strings, what is the best choice: StringBuilder, string concattenation, or string.Format()? So before we being I read in a number of iterations from the console and a length of each string to generate.  Then I generate that many random strings of the given length and an array to hold the results.  Why am I so keen to keep the results?  Because I want to be able to snapshot the memory and don’t want garbage collection to collect the strings, hence the array to keep hold of them.  I also didn’t want the random strings to be part of the allocation, so I pre-allocate them and the array up front before the snapshot.  So in the code snippets below: num – Number of iterations. strings – Array of randomly generated strings. results – Array to hold the results of the concatenation tests. timer – A System.Diagnostics.Stopwatch() instance to time code execution. start – Beginning memory size. stop – Ending memory size. after – Memory size after final GC. So first, let’s look at the concatenation loop: 1: // build num strings using concattenation. 2: for (int i = 0; i < num; i++) 3: { 4: results[i] = "This is test #" + i + " with a result of " + strings[i]; 5: } Pretty standard, right?  Next for string.Format(): 1: // build strings using string.Format() 2: for (int i = 0; i < num; i++) 3: { 4: results[i] = string.Format("This is test #{0} with a result of {1}", i, strings[i]); 5: }   Finally, StringBuilder: 1: // build strings using StringBuilder 2: for (int i = 0; i < num; i++) 3: { 4: var builder = new StringBuilder(); 5: builder.Append("This is test #"); 6: builder.Append(i); 7: builder.Append(" with a result of "); 8: builder.Append(strings[i]); 9: results[i] = builder.ToString(); 10: } So I take each of these loops, and time them by using a block like this: 1: // get the total amount of memory used, true tells it to run GC first. 2: start = System.GC.GetTotalMemory(true); 3:  4: // restart the timer 5: timer.Reset(); 6: timer.Start(); 7:  8: // *** code to time and measure goes here. *** 9:  10: // get the current amount of memory, stop the timer, then get memory after GC. 11: stop = System.GC.GetTotalMemory(false); 12: timer.Stop(); 13: other = System.GC.GetTotalMemory(true); So let’s look at what happens when I run each of these blocks through the timer and memory check at 500,000 iterations: 1: Operator + - Time: 547, Memory: 56104540/55595960 - 500000 2: string.Format() - Time: 749, Memory: 57295812/55595960 - 500000 3: StringBuilder - Time: 608, Memory: 55312888/55595960 – 500000   Egad!  string.Format brings up the rear and + triumphs, well, at least in terms of speed.  The concat burns more memory than StringBuilder but less than string.Format().  This shows two main things: StringBuilder is not always the panacea many think it is. The difference between any of the three is miniscule! The second point is extremely important!  You will often here people who will grasp at results and say, “look, operator + is 10% faster than StringBuilder so always use StringBuilder.”  Statements like this are a disservice and often misleading.  For example, if I had a good guess at what the size of the string would be, I could have preallocated my StringBuffer like so:   1: for (int i = 0; i < num; i++) 2: { 3: // pre-declare StringBuilder to have 100 char buffer. 4: var builder = new StringBuilder(100); 5: builder.Append("This is test #"); 6: builder.Append(i); 7: builder.Append(" with a result of "); 8: builder.Append(strings[i]); 9: results[i] = builder.ToString(); 10: }   Now let’s look at the times: 1: Operator + - Time: 551, Memory: 56104412/55595960 - 500000 2: string.Format() - Time: 753, Memory: 57296484/55595960 - 500000 3: StringBuilder - Time: 525, Memory: 59779156/55595960 - 500000   Whoa!  All of the sudden StringBuilder is back on top again!  But notice, it takes more memory now.  This makes perfect sense if you examine the IL behind the scenes.  Whenever you do a string concat (+) in your code, it examines the lengths of the arguments and creates a StringBuilder behind the scenes of the appropriate size for you. But even IF we know the approximate size of our StringBuilder, look how much less readable it is!  That’s why I feel you should always take into account both readability and performance.  After all, consider all these timings are over 500,000 iterations.   That’s at best  0.0004 ms difference per call which is neglidgable at best.  The key is to pick the best tool for the job.  What do I mean?  Consider these awesome words of wisdom: Concatenate (+) is best at concatenating.  StringBuilder is best when you need to building. Format is best at formatting. Totally Earth-shattering, right!  But if you consider it carefully, it actually has a lot of beauty in it’s simplicity.  Remember, there is no magic bullet.  If one of these always beat the others we’d only have one and not three choices. The fact is, the concattenation operator (+) has been optimized for speed and looks the cleanest for joining together a known set of strings in the simplest manner possible. StringBuilder, on the other hand, excels when you need to build a string of inderterminant length.  Use it in those times when you are looping till you hit a stop condition and building a result and it won’t steer you wrong. String.Format seems to be the looser from the stats, but consider which of these is more readable.  Yes, ignore the fact that you could do this with ToString() on a DateTime.  1: // build a date via concatenation 2: var date1 = (month < 10 ? string.Empty : "0") + month + '/' 3: + (day < 10 ? string.Empty : "0") + '/' + year; 4:  5: // build a date via string builder 6: var builder = new StringBuilder(10); 7: if (month < 10) builder.Append('0'); 8: builder.Append(month); 9: builder.Append('/'); 10: if (day < 10) builder.Append('0'); 11: builder.Append(day); 12: builder.Append('/'); 13: builder.Append(year); 14: var date2 = builder.ToString(); 15:  16: // build a date via string.Format 17: var date3 = string.Format("{0:00}/{1:00}/{2:0000}", month, day, year); 18:  So the strength in string.Format is that it makes constructing a formatted string easy to read.  Yes, it’s slower, but look at how much more elegant it is to do zero-padding and anything else string.Format does. So my lesson is, don’t look for the silver bullet!  Choose the best tool.  Micro-optimization almost always bites you in the end because you’re sacrificing readability for performance, which is almost exactly the wrong choice 90% of the time. I love the rules of optimization.  They’ve been stated before in many forms, but here’s how I always remember them: For Beginners: Do not optimize. For Experts: Do not optimize yet. It’s so true.  Most of the time on today’s modern hardware, a micro-second optimization at the sake of readability will net you nothing because it won’t be your bottleneck.  Code for readability, choose the best tool for the job which will usually be the most readable and maintainable as well.  Then, and only then, if you need that extra performance boost after profiling your code and exhausting all other options… then you can start to think about optimizing.

  Read the article

• C#/.NET Little Wonders: The EventHandler and EventHandler&lt;TEventArgs&gt; delegates

  - by James Michael Hare

  Once again, in this series of posts I look at the parts of the .NET Framework that may seem trivial, but can help improve your code by making it easier to write and maintain. The index of all my past little wonders posts can be found here. In the last two weeks, we examined the Action family of delegates (and delegates in general), and the Func family of delegates and how they can be used to support generic, reusable algorithms and classes. So this week, we are going to look at a handy pair of delegates that can be used to eliminate the need for defining custom delegates when creating events: the EventHandler and EventHandler<TEventArgs> delegates. Events and delegates Before we begin, let’s quickly consider events in .NET.  According to the MSDN: An event in C# is a way for a class to provide notifications to clients of that class when some interesting thing happens to an object. So, basically, you can create an event in a type so that users of that type can subscribe to notifications of things of interest.  How is this different than some of the delegate programming that we talked about in the last two weeks?  Well, you can think of an event as a special access modifier on a delegate.  Some differences between the two are: Events are a special access case of delegates They behave much like delegates instances inside the type they are declared in, but outside of that type they can only be (un)subscribed to. Events can specify add/remove behavior explicitly If you want to do additional work when someone subscribes or unsubscribes to an event, you can specify the add and remove actions explicitly. Events have access modifiers, but these only specify the access level of those who can (un)subscribe A public event, for example, means anyone can (un)subscribe, but it does not mean that anyone can raise (invoke) the event directly.  Events can only be raised by the type that contains them In contrast, if a delegate is visible, it can be invoked outside of the object (not even in a sub-class!). Events tend to be for notifications only, and should be treated as optional Semantically speaking, events typically don’t perform work on the the class directly, but tend to just notify subscribers when something of note occurs. My basic rule-of-thumb is that if you are just wanting to notify any listeners (who may or may not care) that something has happened, use an event.  However, if you want the caller to provide some function to perform to direct the class about how it should perform work, make it a delegate. Declaring events using custom delegates To declare an event in a type, we simply use the event keyword and specify its delegate type.  For example, let’s say you wanted to create a new TimeOfDayTimer that triggers at a given time of the day (as opposed to on an interval).  We could write something like this: 1: public delegate void TimeOfDayHandler(object source, ElapsedEventArgs e); 2:  3: // A timer that will fire at time of day each day. 4: public class TimeOfDayTimer : IDisposable 5: { 6: // Event that is triggered at time of day. 7: public event TimeOfDayHandler Elapsed; 8:  9: // ... 10: } The first thing to note is that the event is a delegate type, which tells us what types of methods may subscribe to it.  The second thing to note is the signature of the event handler delegate, according to the MSDN: The standard signature of an event handler delegate defines a method that does not return a value, whose first parameter is of type Object and refers to the instance that raises the event, and whose second parameter is derived from type EventArgs and holds the event data. If the event does not generate event data, the second parameter is simply an instance of EventArgs. Otherwise, the second parameter is a custom type derived from EventArgs and supplies any fields or properties needed to hold the event data. So, in a nutshell, the event handler delegates should return void and take two parameters: An object reference to the object that raised the event. An EventArgs (or a subclass of EventArgs) reference to event specific information. Even if your event has no additional information to provide, you are still expected to provide an EventArgs instance.  In this case, feel free to pass the EventArgs.Empty singleton instead of creating new instances of EventArgs (to avoid generating unneeded memory garbage). The EventHandler delegate Because many events have no additional information to pass, and thus do not require custom EventArgs, the signature of the delegates for subscribing to these events is typically: 1: // always takes an object and an EventArgs reference 2: public delegate void EventHandler(object sender, EventArgs e) It would be insane to recreate this delegate for every class that had a basic event with no additional event data, so there already exists a delegate for you called EventHandler that has this very definition!  Feel free to use it to define any events which supply no additional event information: 1: public class Cache 2: { 3: // event that is raised whenever the cache performs a cleanup 4: public event EventHandler OnCleanup; 5:  6: // ... 7: } This will handle any event with the standard EventArgs (no additional information).  But what of events that do need to supply additional information?  Does that mean we’re out of luck for subclasses of EventArgs?  That’s where the generic for of EventHandler comes into play… The generic EventHandler<TEventArgs> delegate Starting with the introduction of generics in .NET 2.0, we have a generic delegate called EventHandler<TEventArgs>.  Its signature is as follows: 1: public delegate void EventHandler<TEventArgs>(object sender, TEventArgs e) 2: where TEventArgs : EventArgs This is similar to EventHandler except it has been made generic to support the more general case.  Thus, it will work for any delegate where the first argument is an object (the sender) and the second argument is a class derived from EventArgs (the event data). For example, let’s say we wanted to create a message receiver, and we wanted it to have a few events such as OnConnected that will tell us when a connection is established (probably with no additional information) and OnMessageReceived that will tell us when a new message arrives (probably with a string for the new message text). So for OnMessageReceived, our MessageReceivedEventArgs might look like this: 1: public sealed class MessageReceivedEventArgs : EventArgs 2: { 3: public string Message { get; set; } 4: } And since OnConnected needs no event argument type defined, our class might look something like this: 1: public class MessageReceiver 2: { 3: // event that is called when the receiver connects with sender 4: public event EventHandler OnConnected; 5:  6: // event that is called when a new message is received. 7: public event EventHandler<MessageReceivedEventArgs> OnMessageReceived; 8:  9: // ... 10: } Notice, nowhere did we have to define a delegate to fit our event definition, the EventHandler and generic EventHandler<TEventArgs> delegates fit almost anything we’d need to do with events. Sidebar: Thread-safety and raising an event When the time comes to raise an event, we should always check to make sure there are subscribers, and then only raise the event if anyone is subscribed.  This is important because if no one is subscribed to the event, then the instance will be null and we will get a NullReferenceException if we attempt to raise the event. 1: // This protects against NullReferenceException... or does it? 2: if (OnMessageReceived != null) 3: { 4: OnMessageReceived(this, new MessageReceivedEventArgs(aMessage)); 5: } The above code seems to handle the null reference if no one is subscribed, but there’s a problem if this is being used in multi-threaded environments.  For example, assume we have thread A which is about to raise the event, and it checks and clears the null check and is about to raise the event.  However, before it can do that thread B unsubscribes to the event, which sets the delegate to null.  Now, when thread A attempts to raise the event, this causes the NullReferenceException that we were hoping to avoid! To counter this, the simplest best-practice method is to copy the event (just a multicast delegate) to a temporary local variable just before we raise it.  Since we are inside the class where this event is being raised, we can copy it to a local variable like this, and it will protect us from multi-threading since multicast delegates are immutable and assignments are atomic: 1: // always make copy of the event multi-cast delegate before checking 2: // for null to avoid race-condition between the null-check and raising it. 3: var handler = OnMessageReceived; 4: 5: if (handler != null) 6: { 7: handler(this, new MessageReceivedEventArgs(aMessage)); 8: } The very slight trade-off is that it’s possible a class may get an event after it unsubscribes in a multi-threaded environment, but this is a small risk and classes should be prepared for this possibility anyway.  For a more detailed discussion on this, check out this excellent Eric Lippert blog post on Events and Races. Summary Generic delegates give us a lot of power to make generic algorithms and classes, and the EventHandler delegate family gives us the flexibility to create events easily, without needing to redefine delegates over and over.  Use them whenever you need to define events with or without specialized EventArgs.   Tweet Technorati Tags: .NET, C#, CSharp, Little Wonders, Generics, Delegates, EventHandler

  Read the article

• That Escalated Quickly

  - by Jesse Taber

  Originally posted on: http://geekswithblogs.net/GruffCode/archive/2014/05/17/that-escalated-quickly.aspxI have been working remotely out of my home for over 4 years now. All of my coworkers during that time have also worked remotely. Lots of folks have written about the challenges inherent in facilitating communication on remote teams and strategies for overcoming them. A popular theme around this topic is the notion of “escalating communication”. In this context “escalating” means taking a conversation from one mode of communication to a different, higher fidelity mode of communication. Here are the five modes of communication I use at work in order of increasing fidelity: Email – This is the “lowest fidelity” mode of communication that I use. I usually only check it a few times a day (and I’m trying to check it even less frequently than that) and I only keep items in my inbox if they represent an item I need to take action on that I haven’t tracked anywhere else. Forums / Message boards – Being a developer, I’ve gotten into the habit of having other people look over my code before it becomes part of the product I’m working on. These code reviews often happen in “real time” via screen sharing, but I also always have someone else give all of the changes another look using pull requests. A pull request takes my code and lets someone else see the changes I’ve made side-by-side with the existing code so they can see if I did anything dumb. Pull requests can facilitate a conversation about the code changes in an online-forum like style. Some teams I’ve worked on also liked using tools like Trello or Google Groups to have on-going conversations about a topic or task that was being worked on. Chat & Instant Messaging  - Chat and instant messaging are the real workhorses for communication on the remote teams I’ve been a part of. I know some teams that are co-located that also use it pretty extensively for quick messages that don’t warrant walking across the office to talk with someone but reqire more immediacy than an e-mail. For the purposes of this post I think it’s important to note that the terms “chat” and “instant messaging” might insinuate that the conversation is happening in real time, but that’s not always true. Modern chat and IM applications maintain a searchable history so people can easily see what might have been discussed while they were away from their computers. Voice, Video and Screen sharing – Everyone’s got a camera and microphone on their computers now, and there are an abundance of services that will let you use them to talk to other people who have cameras and microphones on their computers. I’m including screen sharing here as well because, in my experience, these discussions typically involve one or more people showing the other participants something that’s happening on their screen. Obviously, this mode of communication is much higher-fidelity than any of the ones listed above. Scheduled meetings are typically conducted using this mode of communication. In Person – No matter how great communication tools become, there’s no substitute for meeting with someone face-to-face. However, opportunities for this kind of communcation are few and far between when you work on a remote team. When a conversation gets escalated that usually means it moves up one or more positions on this list. A lot of people advocate jumping to #4 sooner than later. Like them, I used to believe that, if it was possible, organizing a call with voice and video was automatically better than any kind of text-based communication could be. Lately, however, I’m becoming less convinced that escalating is always the right move. Working Asynchronously Last year I attended a talk at our local code camp given by Drew Miller. Drew works at GitHub and was talking about how they use GitHub internally. Many of the folks at GitHub work remotely, so communication was one of the main themes in Drew’s talk. During the talk Drew used the phrase, “asynchronous communication” to describe their use of chat and pull request comments. That phrase stuck in my head because I hadn’t heard it before but I think it perfectly describes the way in which remote teams often need to communicate. You don’t always know when your co-workers are at their computers or what hours (if any) they are working that day. In order to work this way you need to assume that the person you’re talking to might not respond right away. You can’t always afford to wait until everyone required is online and available to join a voice call, so you need to use text-based, persistent forms of communication so that people can receive and respond to messages when they are available. Going back to my list from the beginning of this post for a second, I characterize items #1-3 as being “asynchronous” modes of communication while we could call items #4 and #5 “synchronous”. When communication gets escalated it’s almost always moving from an asynchronous mode of communication to a synchronous one. Now, to the point of this post: I’ve become increasingly reluctant to escalate from asynchronous to synchronous communication for two primary reasons: 1 – You can often find a higher fidelity way to convey your message without holding a synchronous conversation 2 - Asynchronous modes of communication are (usually) persistent and searchable. You Don’t Have to Broadcast Live Let’s start with the first reason I’ve listed. A lot of times you feel like you need to escalate to synchronous communication because you’re having difficulty describing something that you’re seeing in words. You want to provide the people you’re conversing with some audio-visual aids to help them understand the point that you’re trying to make and you think that getting on Skype and sharing your screen with them is the best way to do that. Firing up a screen sharing session does work well, but you can usually accomplish the same thing in an asynchronous manner. For example, you could take a screenshot and annotate it with some text and drawings to illustrate what it is you’re seeing. If a screenshot won’t work, taking a short screen recording while your narrate over it and posting the video to your forum or chat system along with a text-based description of what’s in the recording that can be searched for later can be a great way to effectively communicate with your team asynchronously. I Said What?!? Now for the second reason I listed: most asynchronous modes of communication provide a transcript of what was said and what decisions might have been made during the conversation. There have been many occasions where I’ve used the search feature of my team’s chat application to find a conversation that happened several weeks or months ago to remember what was decided. Unfortunately, I think the benefits associated with the persistence of communicating asynchronously often get overlooked when people decide to escalate to a in-person meeting or voice/video call. I’m becoming much more reluctant to suggest a voice or video call if I suspect that it might lead to codifying some kind of design decision because everyone involved is going to hang up the call and immediately forget what was decided. I recognize that you can record and archive these types of interactions, but without being able to search them the recordings aren’t terribly useful. When and How To Escalate I don’t mean to imply that communicating via voice/video or in person is never a good idea. I probably jump on a Skype call with a co-worker at least once a day to quickly hash something out or show them a bit of code that I’m working on. Also, meeting in person periodically is really important for remote teams. There’s no way around the fact that sometimes it’s easier to jump on a call and show someone my screen so they can see what I’m seeing. So when is it right to escalate? I think the simplest way to answer that is when the communication starts to feel painful. Everyone’s tolerance for that pain is different, but I think you need to let it hurt a little bit before jumping to synchronous communication. When you do escalate from asynchronous to synchronous communication, there are a couple of things you can do to maximize the effectiveness of the communication: Takes notes – This is huge and yet I’ve found that a lot of teams don’t do this. If you’re holding a meeting with  > 2 people you should have someone taking notes. Taking notes while participating in a meeting can be difficult but there are a few strategies to deal with this challenge that probably deserve a short post of their own. After the meeting, make sure the notes are posted to a place where all concerned parties (including those that might not have attended the meeting) can review and search them. Persist decisions made ASAP – If any decisions were made during the meeting, persist those decisions to a searchable medium as soon as possible following the conversation. All the teams I’ve worked on used a web-based system for tracking the on-going work and a backlog of work to be done in the future. I always try to make sure that all of the cards/stories/tasks/whatever in these systems always reflect the latest decisions that were made as the work was being planned and executed. If held a quick call with your team lead and decided that it wasn’t worth the effort to build real-time validation into that new UI you were working on, go and codify that decision in the story associated with that work immediately after you hang up. Even better, write it up in the story while you are both still on the phone. That way when the folks from your QA team pick up the story to test a few days later they’ll know why the real-time validation isn’t there without having to invoke yet another conversation about the work. Communicating Well is Hard At this point you might be thinking that communicating asynchronously is more difficult than having a live conversation. You’re right: it is more difficult. In order to communicate effectively this way you need to very carefully think about the message that you’re trying to convey and craft it in a way that’s easy for your audience to understand. This is almost always harder than just talking through a problem in real time with someone; this is why escalating communication is such a popular idea. Why wouldn’t we want to do the thing that’s easier? Easier isn’t always better. If you and your team can get in the habit of communicating effectively in an asynchronous manner you’ll find that, over time, all of your communications get less painful because you don’t need to re-iterate previously made points over and over again. If you communicate right the first time, you often don’t need to rehash old conversations because you can go back and find the decisions that were made laid out in plain language. You’ll also find that you get better at doing things like writing useful comments in your code, creating written documentation about how the feature that you just built works, or persuading your team to do things in a certain way.

  Read the article

• Using Table-Valued Parameters With SQL Server Reporting Services

  - by Jesse

  In my last post I talked about using table-valued parameters to pass a list of integer values to a stored procedure without resorting to using comma-delimited strings and parsing out each value into a TABLE variable. In this post I’ll extend the “Customer Transaction Summary” report example to see how we might leverage this same stored procedure from within an SQL Server Reporting Services (SSRS) report. I’ve worked with SSRS off and on for the past several years and have generally found it to be a very useful tool for building nice-looking reports for end users quickly and easily. That said, I’ve been frustrated by SSRS from time to time when seemingly simple things are difficult to accomplish or simply not supported at all. I thought that using table-valued parameters from within a SSRS report would be simple, but unfortunately I was wrong. Customer Transaction Summary Example Let’s take the “Customer Transaction Summary” report example from the last post and try to plug that same stored procedure into an SSRS report. Our report will have three parameters: Start Date – beginning of the date range for which the report will summarize customer transactions End Date – end of the date range for which the report will summarize customer transactions Customer Ids – One or more customer Ids representing the customers that will be included in the report The simplest way to get started with this report will be to create a new dataset and point it at our Customer Transaction Summary report stored procedure (note that I’m using SSRS 2012 in the screenshots below, but there should be little to no difference with SSRS 2008): When you initially create this dataset the SSRS designer will try to invoke the stored procedure to determine what the parameters and output fields are for you automatically. As part of this process the following dialog pops-up: Obviously I can’t use this dialog to specify a value for the ‘@customerIds’ parameter since it is of the IntegerListTableType user-defined type that we created in the last post. Unfortunately this really throws the SSRS designer for a loop, and regardless of what combination of Data Type, Pass Null Value, or Parameter Value I used here, I kept getting this error dialog with the message, "Operand type clash: nvarchar is incompatible with IntegerListTableType". This error message makes some sense considering that the nvarchar type is indeed incompatible with the IntegerListTableType, but there’s little clue given as to how to remedy the situation. I don’t know for sure, but I think that behind-the-scenes the SSRS designer is trying to give the @customerIds parameter an nvarchar-typed SqlParameter which is causing the issue. When I first saw this error I figured that this might just be a limitation of the dataset designer and that I’d be able to work around the issue by manually defining the parameters. I know that there are some special steps that need to be taken when invoking a stored procedure with a table-valued parameter from ADO .NET, so I figured that I might be able to use some custom code embedded in the report  to create a SqlParameter instance with the needed properties and value to make this work, but the “Operand type clash" error message persisted. The Text Query Approach Just because we’re using a stored procedure to create the dataset for this report doesn’t mean that we can’t use the ‘Text’ Query Type option and construct an EXEC statement that will invoke the stored procedure. In order for this to work properly the EXEC statement will also need to declare and populate an IntegerListTableType variable to pass into the stored procedure. Before I go any further I want to make one point clear: this is a really ugly hack and it makes me cringe to do it. Simply put, I strongly feel that it should not be this difficult to use a table-valued parameter with SSRS. With that said, let’s take a look at what we’ll have to do to make this work. Manually Define Parameters First, we’ll need to manually define the parameters for report by right-clicking on the ‘Parameters’ folder in the ‘Report Data’ window. We’ll need to define the ‘@startDate’ and ‘@endDate’ as simple date parameters. We’ll also create a parameter called ‘@customerIds’ that will be a mutli-valued Integer parameter: In the ‘Available Values’ tab we’ll point this parameter at a simple dataset that just returns the CustomerId and CustomerName of each row in the Customers table of the database or manually define a handful of Customer Id values to make available when the report runs. Once we have these parameters properly defined we can take another crack at creating the dataset that will invoke the ‘rpt_CustomerTransactionSummary’ stored procedure. This time we’ll choose the ‘Text’ query type option and put the following into the ‘Query’ text area: 1: exec('declare @customerIdList IntegerListTableType ' + @customerIdInserts + 2: ' EXEC rpt_CustomerTransactionSummary 3: @startDate=''' + @startDate + ''', 4: @endDate='''+ @endDate + ''', 5: @customerIds=@customerIdList')   By using the ‘Text’ query type we can enter any arbitrary SQL that we we want to and then use parameters and string concatenation to inject pieces of that query at run time. It can be a bit tricky to parse this out at first glance, but from the SSRS designer’s point of view this query defines three parameters: @customerIdInserts – This will be a Text parameter that we use to define INSERT statements that will populate the @customerIdList variable that is being declared in the SQL. This parameter won’t actually ever get passed into the stored procedure. I’ll go into how this will work in a bit. @startDate – This is a simple date parameter that will get passed through directly into the @startDate parameter of the stored procedure on line 3. @endDate – This is another simple data parameter that will get passed through into the @endDate parameter of the stored procedure on line 4. At this point the dataset designer will be able to correctly parse the query and should even be able to detect the fields that the stored procedure will return without needing to specify any values for query when prompted to. Once the dataset has been correctly defined we’ll have a @customerIdInserts parameter listed in the ‘Parameters’ tab of the dataset designer. We need to define an expression for this parameter that will take the values selected by the user for the ‘@customerIds’ parameter that we defined earlier and convert them into INSERT statements that will populate the @customerIdList variable that we defined in our Text query. In order to do this we’ll need to add some custom code to our report using the ‘Report Properties’ dialog: Any custom code defined in the Report Properties dialog gets embedded into the .rdl of the report itself and (unfortunately) must be written in VB .NET. Note that you can also add references to custom .NET assemblies (which could be written in any language), but that’s outside the scope of this post so we’ll stick with the “quick and dirty” VB .NET approach for now. Here’s the VB .NET code (note that any embedded code that you add here must be defined in a static/shared function, though you can define as many functions as you want): 1: Public Shared Function BuildIntegerListInserts(ByVal variableName As String, ByVal paramValues As Object()) As String 2: Dim insertStatements As New System.Text.StringBuilder() 3: For Each paramValue As Object In paramValues 4: insertStatements.AppendLine(String.Format("INSERT {0} VALUES ({1})", variableName, paramValue)) 5: Next 6: Return insertStatements.ToString() 7: End Function   This method takes a variable name and an array of objects. We use an array of objects here because that is how SSRS will pass us the values that were selected by the user at run-time. The method uses a StringBuilder to construct INSERT statements that will insert each value from the object array into the provided variable name. Once this method has been defined in the custom code for the report we can go back into the dataset designer’s Parameters tab and update the expression for the ‘@customerIdInserts’ parameter by clicking on the button with the “function” symbol that appears to the right of the parameter value. We’ll set the expression to: 1: =Code.BuildIntegerListInserts("@customerIdList ", Parameters!customerIds.Value)   In order to invoke our custom code method we simply need to invoke “Code.<method name>” and pass in any needed parameters. The first parameter needs to match the name of the IntegerListTableType variable that we used in the EXEC statement of our query. The second parameter will come from the Value property of the ‘@customerIds’ parameter (this evaluates to an object array at run time). Finally, we’ll need to edit the properties of the ‘@customerIdInserts’ parameter on the report to mark it as a nullable internal parameter so that users aren’t prompted to provide a value for it when running the report. Limitations And Final Thoughts When I first started looking into the text query approach described above I wondered if there might be an upper limit to the size of the string that can be used to run a report. Obviously, the size of the actual query could increase pretty dramatically if you have a parameter that has a lot of potential values or you need to support several different table-valued parameters in the same query. I tested the example Customer Transaction Summary report with 1000 selected customers without any issue, but your mileage may vary depending on how much data you might need to pass into your query. If you think that the text query hack is a lot of work just to use a table-valued parameter, I agree! I think that it should be a lot easier than this to use a table-valued parameter from within SSRS, but so far I haven’t found a better way. It might be possible to create some custom .NET code that could build the EXEC statement for a given set of parameters automatically, but exploring that will have to wait for another post. For now, unless there’s a really compelling reason or requirement to use table-valued parameters from SSRS reports I would probably stick with the tried and true “join-multi-valued-parameter-to-CSV-and-split-in-the-query” approach for using mutli-valued parameters in a stored procedure.

  Read the article

• How to parametrize WPF Style?

  - by Konstantin

  Hi! I'm looking for a simplest way to remove duplication in my WPF code. Code below is a simple traffic light with 3 lights - Red, Amber, Green. It is bound to a ViewModel that has one enum property State taking one of those 3 values. Code declaring 3 ellipses is very duplicative. Now I want to add animation so that each light fades in and out - styles will become even bigger and duplication will worsen. Is it possible to parametrize style with State and Color arguments so that I can have a single style in resources describing behavior of a light and then use it 3 times - for 'Red', 'Amber' and 'Green' lights? <UserControl.Resources> <l:TrafficLightViewModel x:Key="ViewModel" /> </UserControl.Resources> <StackPanel Orientation="Vertical" DataContext="{StaticResource ViewModel}"> <StackPanel.Resources> <Style x:Key="singleLightStyle" TargetType="{x:Type Ellipse}"> <Setter Property="StrokeThickness" Value="2" /> <Setter Property="Stroke" Value="Black" /> <Setter Property="Height" Value="{Binding Width, RelativeSource={RelativeSource Self}}" /> <Setter Property="Width" Value="60" /> <Setter Property="Fill" Value="LightGray" /> </Style> </StackPanel.Resources> <Ellipse> <Ellipse.Style> <Style TargetType="{x:Type Ellipse}" BasedOn="{StaticResource singleLightStyle}"> <Style.Triggers> <DataTrigger Binding="{Binding State}" Value="Red"> <Setter Property="Fill" Value="Red" /> </DataTrigger> </Style.Triggers> </Style> </Ellipse.Style> </Ellipse> <Ellipse> <Ellipse.Style> <Style TargetType="{x:Type Ellipse}" BasedOn="{StaticResource singleLightStyle}"> <Style.Triggers> <DataTrigger Binding="{Binding State}" Value="Amber"> <Setter Property="Fill" Value="Red" /> </DataTrigger> </Style.Triggers> </Style> </Ellipse.Style> </Ellipse> <Ellipse> <Ellipse.Style> <Style TargetType="{x:Type Ellipse}" BasedOn="{StaticResource singleLightStyle}"> <Style.Triggers> <DataTrigger Binding="{Binding State}" Value="Green"> <Setter Property="Fill" Value="Green" /> </DataTrigger> </Style.Triggers> </Style> </Ellipse.Style> </Ellipse> </StackPanel>

  Read the article

• How I Record Screencasts

  - by Daniel Moth

  I get this asked a lot so here is my brain dump on the topic. What A screencast is just a demo that you present to yourself while recording the screen. As such, my advice for clearing your screen for demo purposes and setting up Visual Studio still applies here (adjusting for the fact I wrote those blog posts when I was running Vista and VS2008, not Windows 8 and VS2012). To see examples of screencasts, watch any of my screencasts on channel9. Why If you are a technical presenter, think of when you get best reactions from a developer audience in your sessions: when you are doing demos, of course. Imagine if you could package those alone and share them with folks to watch over and over? If you have ever gone through a tutorial trying to recreate steps to explore a feature, think how much more helpful it would be if you could watch a video and follow along. Think of how many folks you "touch" with a conference presentation, and how many more you can reach with an online shorter recording of the demo. If you invest so much of your time for the first type of activity, isn't the second type of activity also worth an investment? Fact: If you are able to record a screencast of a demo, you will be much better prepared to deliver it in person. In fact lately I will force myself to make a screencast of any demo I need to present live at an upcoming event. It is also a great backup - if for whatever reason something fails (software, network, etc) during an attempt of a live demo, you can just play the recorded video for the live audience. There are other reasons (e.g. internal sharing of the latest implemented feature) but the context above is the one within which I create most of my screencasts. Software & Hardware I use Camtasia from Tech Smith, version 7.1.1. Microsoft has a variety of options for capturing the screen to video, but I have been using this software for so long now that I have not invested time to explore alternatives… I also use whatever cheapo headset is near me, but sometimes I get some complaints from some folks about the audio so now I try to remember to use "the good headset". I do not use a web camera as I am not a huge fan of PIP. Preparation First you have to know your technology and demo. Once you think you know it, write down the outline and major steps of the demo. Keep it short 5-20 minutes max. I break that rule sometimes but try not to. The longer the video is the more chances that people will not have the patience to sit through it and the larger the download wmv file ends up being. Run your demo a few times, timing yourself each time to ensure that you have the planned timing correct, but also to make sure that you are comfortable with what you are going to demo. Unlike with a live audience, there is no live reaction/feedback to steer you, so it can be a bit unnerving at first. It can also lead you to babble too much, so try extra hard to be succinct when demoing/screencasting on your own. TIP: Before recording, hide your desktop/taskbar clock if it is showing. Recording To record you start the Camtasia Recorder tool Configure the settings thought the menus Capture menu to choose custom size or full screen. I try to use full screen and remember to lower the resolution of your screen to as low as possible, e.g. 1024x768 or 1360x768 or something like that. From the Tools -> Options dialog you can choose to record audio and the volume level. Effects menu I typically leave untouched but you should explore and experiment to your liking, e.g. how the mouse pointer is captured, and whether there should be a delay for the recording when you start it. Once you've configured these settings, typically you just launch this tool and hit the F9 key to start recording. TIP: As you record, if you ever start to "lose your way" hit F9 again to pause recording, regroup your thoughts and flow, and then hit F9 again to resume. Finally, hit F10 to stop recording. At that point the video starts playing for you in the recorder. This is where you can preview the video to see that you are happy with it before saving. If you are happy, hit the Save As menu to choose where you want to save the video.     TIP: If you've really lost your way to the extent where you'll need to do some editing, hit F10 to stop recording, save the video and then record some more - you'll be able to stitch the videos together later and this will make it easier for you to delete the parts where you messed up. TIP: Before you commit to recording the whole demo, every time you should record 5 seconds and preview them to ensure that you are capturing the screen the way you want to and that your audio is still correctly configured and at the right level. Trust me, you do not want to be recording 15 minutes only to find out that you messed up on the configuration somewhere. Editing To edit the video you launch another Camtasia app, the Camtasia Studio. File->New Project. File->Save Project and choose location. File->Import Media and choose the video(s) you saved earlier. These adds them to the area at the top/middle but not at the timeline at the bottom. Right click on the video and choose Add to timeline. It will prompt you for the Editing dimensions and I always choose Recording Dimensions. Do whatever edits you want to do for this video, then add the next video if you have one to stitch and repeat. In terms of edits there are many options. The simplest is to do nothing, which is the option I did when I first starting doing these in 2006. Nowadays, I typically cut out pieces that I don't like and also lower/mute the audio in other areas and also speed up the video in some areas. A full tutorial on how to do this is beyond the scope of this blog post, but your starting point is to select portions on the timeline and then open the Edit menu at the very top (tip: the context menu doesn't have all options). You can spend hours editing a recording, so don’t lose track of time! When you are done editing, save again, and you are now ready to Produce. Producing Production is specific to where you will publish. I've only ever published on channel9, so for that I do the following File -> Produce and share. This opens a wizard dialog In the dropdown choose Custom production settings Hit Next and then choose WMV Hit Next and keep the default of Camtasia Studio Best Quality and File Size (recommended) Hit Next and choose Editing dimensions video size Hit Next, hit Options and you get a dialog. Enter a Title for the project tab and then on the author tab enter the Creator and Homepage. Hit OK Hit Next. Hit Next again. Enter a video file name in the Production name textbox and then hit Finish. Now do other stuff while you wait for the video to be produced and you hear it playing. After the video is produced watch it to ensure it was produced correctly (e.g. sometimes you get mouse issues) and then you are ready for publishing it. Publishing Follow the instructions of the place where you are going to publish. If you are MSFT internal and want to choose channel9 then contact those folks so they can share their instructions (if you don't know who they are ping me and I'll connect you but they are easy to find in the GAL). For me this involves using a tool to point to the video, choosing a file name (again), choosing an image from the video to display when it is not playing, choosing what output formats I want, and then later on a webpage adding tags, adding a description, and adding a title. That’s all folks, have fun! Comments about this post by Daniel Moth welcome at the original blog.

  Read the article

• Adding an Admin user to an ASP.NET MVC 4 application using a single drop-in file

  - by Jon Galloway

  I'm working on an ASP.NET MVC 4 tutorial and wanted to set it up so just dropping a file in App_Start would create a user named "Owner" and assign them to the "Administrator" role (more explanation at the end if you're interested). There are reasons why this wouldn't fit into most application scenarios: It's not efficient, as it checks for (and creates, if necessary) the user every time the app starts up The username, password, and role name are hardcoded in the app (although they could be pulled from config) Automatically creating an administrative account in code (without user interaction) could lead to obvious security issues if the user isn't informed However, with some modifications it might be more broadly useful - e.g. creating a test user with limited privileges, ensuring a required account isn't accidentally deleted, or - as in my case - setting up an account for demonstration or tutorial purposes. Challenge #1: Running on startup without requiring the user to install or configure anything I wanted to see if this could be done just by having the user drop a file into the App_Start folder and go. No copying code into Global.asax.cs, no installing addition NuGet packages, etc. That may not be the best approach - perhaps a NuGet package with a dependency on WebActivator would be better - but I wanted to see if this was possible and see if it offered the best experience. Fortunately ASP.NET 4 and later provide a PreApplicationStartMethod attribute which allows you to register a method which will run when the application starts up. You drop this attribute in your application and give it two parameters: a method name and the type that contains it. I created a static class named PreApplicationTasks with a static method named, then dropped this attribute in it: [assembly: PreApplicationStartMethod(typeof(PreApplicationTasks), "Initializer")] That's it. One small gotcha: the namespace can be a problem with assembly attributes. I decided my class didn't need a namespace. Challenge #2: Only one PreApplicationStartMethod per assembly In .NET 4, the PreApplicationStartMethod is marked as AllMultiple=false, so you can only have one PreApplicationStartMethod per assembly. This was fixed in .NET 4.5, as noted by Jon Skeet, so you can have as many PreApplicationStartMethods as you want (allowing you to keep your users waiting for the application to start indefinitely!). The WebActivator NuGet package solves the multiple instance problem if you're in .NET 4 - it registers as a PreApplicationStartMethod, then calls any methods you've indicated using [assembly: WebActivator.PreApplicationStartMethod(type, method)]. David Ebbo blogged about that here:  Light up your NuGets with startup code and WebActivator. In my scenario (bootstrapping a beginner level tutorial) I decided not to worry about this and stick with PreApplicationStartMethod. Challenge #3: PreApplicationStartMethod kicks in before configuration has been read This is by design, as Phil explains. It allows you to make changes that need to happen very early in the pipeline, well before Application_Start. That's fine in some cases, but it caused me problems when trying to add users, since the Membership Provider configuration hadn't yet been read - I got an exception stating that "Default Membership Provider could not be found." The solution here is to run code that requires configuration in a PostApplicationStart method. But how to do that? Challenge #4: Getting PostApplicationStartMethod without requiring WebActivator The WebActivator NuGet package, among other things, provides a PostApplicationStartMethod attribute. That's generally how I'd recommend running code that needs to happen after Application_Start: [assembly: WebActivator.PostApplicationStartMethod(typeof(TestLibrary.MyStartupCode), "CallMeAfterAppStart")] This works well, but I wanted to see if this would be possible without WebActivator. Hmm. Well, wait a minute - WebActivator works in .NET 4, so clearly it's registering and calling PostApplicationStartup tasks somehow. Off to the source code! Sure enough, there's even a handy comment in ActivationManager.cs which shows where PostApplicationStartup tasks are being registered: public static void Run() { if (!_hasInited) { RunPreStartMethods(); // Register our module to handle any Post Start methods. But outside of ASP.NET, just run them now if (HostingEnvironment.IsHosted) { Microsoft.Web.Infrastructure.DynamicModuleHelper.DynamicModuleUtility.RegisterModule(typeof(StartMethodCallingModule)); } else { RunPostStartMethods(); } _hasInited = true; } } Excellent. Hey, that DynamicModuleUtility seems familiar... Sure enough, K. Scott Allen mentioned it on his blog last year. This is really slick - a PreApplicationStartMethod can register a new HttpModule in code. Modules are run right after application startup, so that's a perfect time to do any startup stuff that requires configuration to be read. As K. Scott says, it's this easy: using System; using System.Web; using Microsoft.Web.Infrastructure.DynamicModuleHelper; [assembly:PreApplicationStartMethod(typeof(MyAppStart), "Start")] public class CoolModule : IHttpModule { // implementation not important // imagine something cool here } public static class MyAppStart { public static void Start() { DynamicModuleUtility.RegisterModule(typeof(CoolModule)); } } Challenge #5: Cooperating with SimpleMembership The ASP.NET MVC Internet template includes SimpleMembership. SimpleMembership is a big improvement over traditional ASP.NET Membership. For one thing, rather than forcing a database schema, it can work with your database schema. In the MVC 4 Internet template case, it uses Entity Framework Code First to define the user model. SimpleMembership bootstrap includes a call to InitializeDatabaseConnection, and I want to play nice with that. There's a new [InitializeSimpleMembership] attribute on the AccountController, which calls \Filters\InitializeSimpleMembershipAttribute.cs::OnActionExecuting(). That comment in that method that says "Ensure ASP.NET Simple Membership is initialized only once per app start" which sounds like good advice. I figured the best thing would be to call that directly: new Mvc4SampleApplication.Filters.InitializeSimpleMembershipAttribute().OnActionExecuting(null); I'm not 100% happy with this - in fact, it's my least favorite part of this solution. There are two problems - first, directly calling a method on a filter, while legal, seems odd. Worse, though, the Filter lives in the application's namespace, which means that this code no longer works well as a generic drop-in. The simplest workaround would be to duplicate the relevant SimpleMembership initialization code into my startup code, but I'd rather not. I'm interested in your suggestions here. Challenge #6: Module Init methods are called more than once When debugging, I noticed (and remembered) that the Init method may be called more than once per page request - it's run once per instance in the app pool, and an individual page request can cause multiple resource requests to the server. While SimpleMembership does have internal checks to prevent duplicate user or role entries, I'd rather not cause or handle those exceptions. So here's the standard single-use lock in the Module's init method: void IHttpModule.Init(HttpApplication context) { lock (lockObject) { if (!initialized) { //Do stuff } initialized = true; } } Putting it all together With all of that out of the way, here's the code I came up with: using Mvc4SampleApplication.Filters; using System.Web; using System.Web.Security; using WebMatrix.WebData; [assembly: PreApplicationStartMethod(typeof(PreApplicationTasks), "Initializer")] public static class PreApplicationTasks { public static void Initializer() { Microsoft.Web.Infrastructure.DynamicModuleHelper.DynamicModuleUtility .RegisterModule(typeof(UserInitializationModule)); } } public class UserInitializationModule : IHttpModule { private static bool initialized; private static object lockObject = new object(); private const string _username = "Owner"; private const string _password = "p@ssword123"; private const string _role = "Administrator"; void IHttpModule.Init(HttpApplication context) { lock (lockObject) { if (!initialized) { new InitializeSimpleMembershipAttribute().OnActionExecuting(null); if (!WebSecurity.UserExists(_username)) WebSecurity.CreateUserAndAccount(_username, _password); if (!Roles.RoleExists(_role)) Roles.CreateRole(_role); if (!Roles.IsUserInRole(_username, _role)) Roles.AddUserToRole(_username, _role); } initialized = true; } } void IHttpModule.Dispose() { } } The Verdict: Is this a good thing? Maybe. I think you'll agree that the journey was undoubtedly worthwhile, as it took us through some of the finer points of hooking into application startup, integrating with membership, and understanding why the WebActivator NuGet package is so useful Will I use this in the tutorial? I'm leaning towards no - I think a NuGet package with a dependency on WebActivator might work better: It's a little more clear what's going on Installing a NuGet package might be a little less error prone than copying a file A novice user could uninstall the package when complete It's a good introduction to NuGet, which is a good thing for beginners to see This code either requires either duplicating a little code from that filter or modifying the file to use the namespace Honestly I'm undecided at this point, but I'm glad that I can weigh the options. If you're interested: Why are you doing this? I'm updating the MVC Music Store tutorial to ASP.NET MVC 4, taking advantage of a lot of new ASP.NET MVC 4 features and trying to simplify areas that are giving people trouble. One change that addresses both needs us using the new OAuth support for membership as much as possible - it's a great new feature from an application perspective, and we get a fair amount of beginners struggling with setting up membership on a variety of database and development setups, which is a distraction from the focus of the tutorial - learning ASP.NET MVC. Side note: Thanks to some great help from Rick Anderson, we had a draft of the tutorial that was looking pretty good earlier this summer, but there were enough changes in ASP.NET MVC 4 all the way up to RTM that there's still some work to be done. It's high priority and should be out very soon. The one issue I ran into with OAuth is that we still need an Administrative user who can edit the store's inventory. I thought about a number of solutions for that - making the first user to register the admin, or the first user to use the username "Administrator" is assigned to the Administrator role - but they both ended up requiring extra code; also, I worried that people would use that code without understanding it or thinking about whether it was a good fit.

  Read the article

• A Simple Approach For Presenting With Code Samples

  - by Jesse Taber

  Originally posted on: http://geekswithblogs.net/GruffCode/archive/2013/07/31/a-simple-approach-for-presenting-with-code-samples.aspxI’ve been getting ready for a presentation and have been struggling a bit with the best way to show and execute code samples. I don’t present often (hardly ever), but when I do I like the presentation to have a lot of succinct and executable code snippets to help illustrate the points that I’m making. Depending on what the presentation is about, I might just want to build an entire sample application that I would run during the presentation. In other cases, however, building a full-blown application might not really be the best way to present the code. The presentation I’m working on now is for an open source utility library for dealing with dates and times. I could have probably cooked up a sample app for accepting date and time input and then contrived ways in which it could put the library through its paces, but I had trouble coming up with one app that would illustrate all of the various features of the library that I wanted to highlight. I finally decided that what I really needed was an approach that met the following criteria: Simple: I didn’t want the user interface or overall architecture of a sample application to serve as a distraction from the demonstration of the syntax of the library that the presentation is about. I want to be able to present small bits of code that are focused on accomplishing a single task. Several of these examples will look similar, and that’s OK. I want each sample to “stand on its own” and not rely much on external classes or methods (other than the library that is being presented, of course). “Debuggable” (not really a word, I know): I want to be able to easily run the sample with the debugger attached in Visual Studio should I want to step through any bits of code and show what certain values might be at run time. As far as I know this rules out something like LinqPad, though using LinqPad to present code samples like this is actually a very interesting idea that I might explore another time. Flexible and Selectable: I’m going to have lots of code samples to show, and I want to be able to just package them all up into a single project or module and have an easy way to just run the sample that I want on-demand. Since I’m presenting on a .NET framework library, one of the simplest ways in which I could execute some code samples would be to just create a Console application and use Console.WriteLine to output the pertinent info at run time. This gives me a “no frills” harness from which to run my code samples, and I just hit ‘F5’ to run it with the debugger. This satisfies numbers 1 and 2 from my list of criteria above, but item 3 is a little harder. By default, just running a console application is going to execute the ‘main’ method, and then terminate the program after all code is executed. If I want to have several different code samples and run them one at a time, it would be cumbersome to keep swapping the code I want in and out of the ‘main’ method of the console application. What I really want is an easy way to keep the console app running throughout the whole presentation and just have it run the samples I want when I want. I could setup a simple Windows Forms or WPF desktop application with buttons for the different samples, but then I’m getting away from my first criteria of keeping things as simple as possible. Infinite Loops To The Rescue I found a way to have a simple console application satisfy all three of my requirements above, and it involves using an infinite loop and some Console.ReadLine calls that will give the user an opportunity to break out and exit the program. (All programs that need to run until they are closed explicitly (or crash!) likely use similar constructs behind the scenes. Create a new Windows Forms project, look in the ‘Program.cs’ that gets generated, and then check out the docs for the Application.Run method that it calls.). Here’s how the main method might look: 1: static void Main(string[] args) 2: { 3: do 4: { 5: Console.Write("Enter command or 'exit' to quit: > "); 6: var command = Console.ReadLine(); 7: if ((command ?? string.Empty).Equals("exit", StringComparison.OrdinalIgnoreCase)) 8: { 9: Console.WriteLine("Quitting."); 10: break; 11: } 12: 13: } while (true); 14: } The idea here is the app prompts me for the command I want to run, or I can type in ‘exit’ to break out of the loop and let the application close. The only trick now is to create a set of commands that map to each of the code samples that I’m going to want to run. Each sample is already encapsulated in a single public method in a separate class, so I could just write a big switch statement or create a hashtable/dictionary that maps command text to an Action that will invoke the proper method, but why re-invent the wheel? CLAP For Your Own Presentation I’ve blogged about the CLAP library before, and it turns out that it’s a great fit for satisfying criteria #3 from my list above. CLAP lets you decorate methods in a class with an attribute and then easily invoke those methods from within a console application. CLAP was designed to take the arguments passed into the console app from the command line and parse them to determine which method to run and what arguments to pass to that method, but there’s no reason you can’t re-purpose it to accept command input from within the infinite loop defined above and invoke the corresponding method. Here’s how you might define a couple of different methods to contain two different code samples that you want to run during your presentation: 1: public static class CodeSamples 2: { 3: [Verb(Aliases="one")] 4: public static void SampleOne() 5: { 6: Console.WriteLine("This is sample 1"); 7: } 8:   9: [Verb(Aliases="two")] 10: public static void SampleTwo() 11: { 12: Console.WriteLine("This is sample 2"); 13: } 14: } A couple of things to note about the sample above: I’m using static methods. You don’t actually need to use static methods with CLAP, but the syntax ends up being a bit simpler and static methods happen to lend themselves well to the “one self-contained method per code sample” approach that I want to use. The methods are decorated with a ‘Verb’ attribute. This tells CLAP that they are eligible targets for commands. The “Aliases” argument lets me give them short and easy-to-remember aliases that can be used to invoke them. By default, CLAP just uses the full method name as the command name, but with aliases you can simply the usage a bit. I’m not using any parameters. CLAP’s main feature is its ability to parse out arguments from a command line invocation of a console application and automatically pass them in as parameters to the target methods. My code samples don’t need parameters ,and honestly having them would complicate giving the presentation, so this is a good thing. You could use this same approach to invoke methods with parameters, but you’d have a couple of things to figure out. When you invoke a .NET application from the command line, Windows will parse the arguments and pass them in as a string array (called ‘args’ in the boilerplate console project Program.cs). The parsing that gets done here is smart enough to deal with things like treating strings in double quotes as one argument, and you’d have to re-create that within your infinite loop if you wanted to use parameters. I plan on either submitting a pull request to CLAP to add this capability or maybe just making a small utility class/extension method to do it and posting that here in the future. So I now have a simple class with static methods to contain my code samples, and an infinite loop in my ‘main’ method that can accept text commands. Wiring this all up together is pretty easy: 1: static void Main(string[] args) 2: { 3: do 4: { 5: try 6: { 7: Console.Write("Enter command or 'exit' to quit: > "); 8: var command = Console.ReadLine(); 9: if ((command ?? string.Empty).Equals("exit", StringComparison.OrdinalIgnoreCase)) 10: { 11: Console.WriteLine("Quitting."); 12: break; 13: } 14:   15: Parser.Run<CodeSamples>(new[] { command }); 16: Console.WriteLine("---------------------------------------------------------"); 17: } 18: catch (Exception ex) 19: { 20: Console.Error.WriteLine("Error: " + ex.Message); 21: } 22:   23: } while (true); 24: } Note that I’m now passing the ‘CodeSamples’ class into the CLAP ‘Parser.Run’ as a type argument. This tells CLAP to inspect that class for methods that might be able to handle the commands passed in. I’m also throwing in a little “----“ style line separator and some basic error handling (because I happen to know that some of the samples are going to throw exceptions for demonstration purposes) and I’m good to go. Now during my presentation I can just have the console application running the whole time with the debugger attached and just type in the alias of the code sample method that I want to run when I want to run it.

  Read the article

• Ajax-based data loading using jQuery.load() function in ASP.NET

  - by hajan

  In general, jQuery has made Ajax very easy by providing low-level interface, shorthand methods and helper functions, which all gives us great features of handling Ajax requests in our ASP.NET Webs. The simplest way to load data from the server and place the returned HTML in browser is to use the jQuery.load() function. The very firs time when I started playing with this function, I didn't believe it will work that much easy. What you can do with this method is simply call given url as parameter to the load function and display the content in the selector after which this function is chained. So, to clear up this, let me give you one very simple example: $("#result").load("AjaxPages/Page.html"); As you can see from the above image, after clicking the ‘Load Content’ button which fires the above code, we are making Ajax Get and the Response is the entire page HTML. So, rather than using (old) iframes, you can now use this method to load other html pages inside the page from where the script with load function is called. This method is equivalent to the jQuery Ajax Get method $.get(url, data, function () { }) only that the $.load() is method rather than global function and has an implicit callback function. To provide callback to your load, you can simply add function as second parameter, see example: $("#result").load("AjaxPages/Page.html", function () { alert("Page.html has been loaded successfully!") }); Since load is part of the chain which is follower of the given jQuery Selector where the content should be loaded, it means that the $.load() function won't execute if there is no such selector found within the DOM. Another interesting thing to mention, and maybe you've asked yourself is how we know if GET or POST method type is executed? It's simple, if we provide 'data' as second parameter to the load function, then POST is used, otherwise GET is assumed. POST $("#result").load("AjaxPages/Page.html", { "name": "hajan" }, function () { ////callback function implementation });   GET $("#result").load("AjaxPages/Page.html", function () { ////callback function implementation });   Another important feature that $.load() has ($.get() does not) is loading page fragments. Using jQuery's selector capability, you can do this: $("#result").load("AjaxPages/Page.html #resultTable"); In our Page.html, the content now is: So, after the call, only the table with id resultTable will load in our page.   As you can see, we have loaded only the table with id resultTable (1) inside div with id result (2). This is great feature since we won't need to filter the returned HTML content again in our callback function on the master page from where we have called $.load() function. Besides the fact that you can simply call static HTML pages, you can also use this function to load dynamic ASPX pages or ASP.NET ASHX Handlers . Lets say we have another page (ASPX) in our AjaxPages folder with name GetProducts.aspx. This page has repeater control (or anything you want to bind dynamic server-side content) that displays set of data in it. Now, I want to filter the data in the repeater based on the Query String parameter provided when calling that page. For example, if I call the page using GetProducts.aspx?category=computers, it will load only computers… so, this will filter the products automatically by given category. The example ASPX code of GetProducts.aspx page is: <%@ Page Language="C#" AutoEventWireup="true" CodeBehind="GetProducts.aspx.cs" Inherits="WebApplication1.AjaxPages.GetProducts" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head runat="server"> <title></title> </head> <body> <form id="form1" runat="server"> <div> <table id="tableProducts"> <asp:Repeater ID="rptProducts" runat="server"> <HeaderTemplate> <tr> <th>Product</th> <th>Price</th> <th>Category</th> </tr> </HeaderTemplate> <ItemTemplate> <tr> <td> <%# Eval("ProductName")%> </td> <td> <%# Eval("Price") %> </td> <td> <%# Eval("Category") %> </td> </tr> </ItemTemplate> </asp:Repeater> </ul> </div> </form> </body> </html> The C# code-behind sample code is: public partial class GetProducts : System.Web.UI.Page { public List<Product> products; protected override void OnInit(EventArgs e) { LoadSampleProductsData(); //load sample data base.OnInit(e); } protected void Page_Load(object sender, EventArgs e) { if (Request.QueryString.Count > 0) { if (!string.IsNullOrEmpty(Request.QueryString["category"])) { string category = Request.QueryString["category"]; //get query string into string variable //filter products sample data by category using LINQ //and add the collection as data source to the repeater rptProducts.DataSource = products.Where(x => x.Category == category); rptProducts.DataBind(); //bind repeater } } } //load sample data method public void LoadSampleProductsData() { products = new List<Product>(); products.Add(new Product() { Category = "computers", Price = 200, ProductName = "Dell PC" }); products.Add(new Product() { Category = "shoes", Price = 90, ProductName = "Nike" }); products.Add(new Product() { Category = "shoes", Price = 66, ProductName = "Adidas" }); products.Add(new Product() { Category = "computers", Price = 210, ProductName = "HP PC" }); products.Add(new Product() { Category = "shoes", Price = 85, ProductName = "Puma" }); } } //sample Product class public class Product { public string ProductName { get; set; } public decimal Price { get; set; } public string Category { get; set; } } Mainly, I just have sample data loading function, Product class and depending of the query string, I am filtering the products list using LINQ Where statement. If we run this page without query string, it will show no data. If we call the page with category query string, it will filter automatically. Example: /AjaxPages/GetProducts.aspx?category=shoes The result will be: or if we use category=computers, like this /AjaxPages/GetProducts.aspx?category=computers, the result will be: So, now using jQuery.load() function, we can call this page with provided query string parameter and load appropriate content… The ASPX code in our Default.aspx page, which will call the AjaxPages/GetProducts.aspx page using jQuery.load() function is: <asp:RadioButtonList ID="rblProductCategory" runat="server"> <asp:ListItem Text="Shoes" Value="shoes" Selected="True" /> <asp:ListItem Text="Computers" Value="computers" /> </asp:RadioButtonList> <asp:Button ID="btnLoadProducts" runat="server" Text="Load Products" /> <!-- Here we will load the products, based on the radio button selection--> <div id="products"></div> </form> The jQuery code: $("#<%= btnLoadProducts.ClientID %>").click(function (event) { event.preventDefault(); //preventing button's default behavior var selectedRadioButton = $("#<%= rblProductCategory.ClientID %> input:checked").val(); //call GetProducts.aspx with the category query string for the selected category in radio button list //filter and get only the #tableProducts content inside #products div $("#products").load("AjaxPages/GetProducts.aspx?category=" + selectedRadioButton + " #tableProducts"); }); The end result: You can download the code sample from here. You can read more about jQuery.load() function here. I hope this was useful blog post for you. Please do let me know your feedback. Best Regards, Hajan

  Read the article

• CodePlex Daily Summary for Monday, November 12, 2012

  CodePlex Daily Summary for Monday, November 12, 2012Popular ReleasesAX 2012 Custom Operating Units: AXPOM (beta): This is beta version of the tool. There are some known issues that will be fixed in the next upcoming release.????: ???? 1.0: ????Unicode IVS Add-in for Microsoft Office: Unicode IVS Add-in for Microsoft Office: Unicode IVS Add-in for Microsoft Office ??? ?????、Unicode IVS?????????????????Unicode IVS???????????????。??、??????????????、?????????????????????????????。EXCEL??、??、????????：DataPie（??MSSQL 2008、ORACLE、ACCESS 2007）: DatePie3.4.2: DatePie3.4.2Microsoft Ajax Minifier: Microsoft Ajax Minifier 4.74: fix for issue #18836 - sometimes throws null-reference errors in ActivationObject.AnalyzeScope method. add back the Context object's 8-parameter constructor, since someone has code that's using it. throw a low-pri warning if an expression statement is == or ===; warn that the developer may have meant an assignment (=). if window.XXXX or window"XXXX" is encountered, add XXXX (as long as it's a valid JavaScript identifier) to the known globals so subsequent references to XXXX won't throw ...Home Access Plus+: v8.3: Changes: Fixed: A odd scroll bar showing up for no reason Changed: Added some code to hopefully sort out the details view when there is a small number of files Fixed: Where the details toolbar shows in the wrong place until you scroll Fixed: Where the Help Desk live tile shows all open tiles, instead of user specific tiles (admins still see all) Added: Powerpoint Files Filter Added: Print style for Booking System Added: Silent check for the logon tracker Updated: Logon Tracker I...Silverlight 4 & 5 Persian DatePicker: Silverlight 4 and 5 Persian DatePicker 1.5: - Improved DateTime Parser.???????: Monitor 2012-11-11: This is the first releaseVidCoder: 1.4.5 Beta: Removed the old Advanced user interface and moved x264 preset/profile/tune there instead. The functionality is still available through editing the options string. Added ability to specify the H.264 level. Added ability to choose VidCoder's interface language. If you are interested in translating, we can get VidCoder in your language! Updated WPF text rendering to use the better Display mode. Updated HandBrake core to SVN 5045. Removed logic that forced the .m4v extension in certain ...ImageGlass: Version 1.5: http://i1214.photobucket.com/albums/cc483/phapsuxeko/ImageGlass/1.png v1.5.4401.3015 Thumbnail bar: Increase loading speed Thumbnail image with ratio Support personal customization: mouse up, mouse down, mouse hover, selected item... Scroll to show all items Image viewer Zoom by scroll, or selected rectangle Speed up loading Zoom to cursor point New background design and customization and others... v1.5.4430.483 Thumbnail bar: Auto move scroll bar to selected image Show / Hi...Building Windows 8 Apps with C# and XAML: Full Source Chapters 1 - 10 for Windows 8 Fix 002: This is the full source from all chapters of the book, compiled and tested on Windows 8 RTM. Includes: A fix for the Netflix example from Chapter 6 that was missing a service reference A fix for the ImageHelper issue (images were not being saved) - this was due to the buffer being inadequate and required streaming the writeable bitmap to a buffer first before encoding and savingmyCollections: Version 2.3.2.0: New in this version : Added TheGamesDB.net API for Games and NDS Added Support for Windows Media Center Added Support for myMovies Added Support for XBMC Added Support for Dune HD Added Support for Mede8er Added Support for WD HDTV Added Fast search options Added order by Artist/Album for music You can now create covers and background for games You can now update your ID3 tag with the info of myCollections Fixed several provider Performance improvement New Splash ...Draw: Draw 1.0: Drawing PadPlayer Framework by Microsoft: Player Framework for Windows 8 (v1.0): IMPORTANT: List of breaking changes from preview 7 Ability to move control panel or individual elements outside media player. more info... New Entertainment app theme for out of the box support for Windows 8 Entertainment app guidelines. more info... VSIX reference names shortened. Allows seeing plugin name from "Add Reference" dialog without resizing. FreeWheel SmartXML now supports new "Standard" event callback type. Other minor misc fixes and improvements ADDITIONAL DOWNLOADSSmo...WebSearch.Net: WebSearch.Net 3.1: WebSearch.Net is an open-source research platform that provides uniform data source access, data modeling, feature calculation, data mining, etc. It facilitates the experiments of web search researchers due to its high flexibility and extensibility. The platform can be used or extended by any language compatible for .Net 2 framework, from C# (recommended), VB.Net to C++ and Java. Thanks to the large coverage of knowledge in web search research, it is necessary to model the techniques and main...Umbraco CMS: Umbraco 4.10.0: NugetNuGet BlogRead the release blog post for 4.10.0. Whats newMVC support New request pipeline Many, many bugfixes (see the issue tracker for a complete list) Read the documentation for the MVC bits. Breaking changesWe have done all we can not to break backwards compatibility, but we had to do some minor breaking changes: Removed graphicHeadlineFormat config setting from umbracoSettings.config (an old relic from the 3.x days) U4-690 DynamicNode ChildrenAsList was fixed, altering it'...SQL Server Partitioned Table Framework: Partitioned Table Framework Release 1.0: SQL Server 2012 ReleaseSharePoint Manager 2013: SharePoint Manager 2013 Release ver 1.0.12.1106: SharePoint Manager 2013 Release (ver: 1.0.12.1106) is now ready for SharePoint 2013. The new version has an expanded view of the SharePoint object model and has been tested on SharePoint 2013 RTM. As a bonus, the new version is also available for SharePoint 2010 as a separate download.Fiskalizacija za developere: FiskalizacijaDev 1.2: Verzija 1.2. je, prije svega, odgovor na novu verziju Tehnicke specifikacije (v1.1.) koja je objavljena prije nekoliko dana. Pored novosti vezanih uz (sitne) izmjene u spomenutoj novoj verziji Tehnicke dokumentacije, projekt smo prošili sa nekim dodatnim feature-ima od kojih je vecina proizašla iz vaših prijedloga - hvala :) Novosti u v1.2. su: - Neusuglašenost zahtjeva (http://fiskalizacija.codeplex.com/workitem/645) - Sample projekt - iznosi se množe sa 100 (http://fiskalizacija.codeplex.c...MFCMAPI: October 2012 Release: Build: 15.0.0.1036 Full release notes at SGriffin's blog. If you just want to run the MFCMAPI or MrMAPI, get the executables. If you want to debug them, get the symbol files and the source. The 64 bit builds will only work on a machine with Outlook 2010 64 bit installed. All other machines should use the 32 bit builds, regardless of the operating system. Facebook BadgeNew Projects.NET C# Wrapper for IQFeed API by Sentinel: An API for DTN IQFeed writtein in C#. Supports: - Historical Data Requests, - Lookup Tables - Level 1 - Level 2 - NewsBaiduMap: ????????API?????Bananagrams: An experimental Java project to find the most efficient strategy of playing Bannagrams, the popular game that I take absolutely no credit for inventing.Cloud Wallet: Don't try to remember every credit card, email, forum and account password of yours. Store them with Cloud Wallet in the skydrive and get them needed.Customer Contact System: System for Local Authorities/Government Bodies to manage enquiries from members of the public in their administrative area.daniel's little electronical bear: Hey, this is Daniel's idea that write her girlfriend a vivid little e-pet. So Daniel is just about to carry on this plan and hopefully fulfill it sooner or later. If you wanna give any advice, please don't hesitate to call me at any time,even ideas is OK!danielzhang0212@gmail.comfacebook page vote and like sample: facebook page vote and like sampleFriendly URL: This application is designed to help large organizations assign simple and memorable URL's to otherwise complicated or non-memorable URL's. GameSDK - Simple Game SDK with events: This game SDK use events for letting know each player through a game board when an events occurs. This is a simple SDK, easily adaptable to your project.GIF o Magic Prototype: GIF o Magic PrototypeHFS+ Driver Installer for Windows: Simple utility to install Read-Only HFS+ Driver to read Mac partitions from Windows.invrt: Simplest-that-could-possibly work inversion of control framework. Written in C#Kwd.Summary: Orchard module to provide alternate summary text for content itemsLogJam: LogJam will provide a modern, efficient, and productive framework for trace logging and metrics logging for all projects. LogJam is currently pre-alpha.Mi-DevEnv: Mi-DevEnv is an integrated set of PowerShell scripts to create virtual machines and populate them with software & tools e.g.: SharePoint,CRM,SQL,Office,K2 & VS.Mltools: mini tools for browser game.More Space Invaders: more then another space invadersMP3 Art Embedder: Embed cover art into MP3 filesMultiple GeoCoder: Serverside geocoding wrapper for various geocoding services. Supports a failover in the event you get throttled.My list: mvc3 project to test some frameworksMyFinalProject_WeamBinjumah: It is a website based on web 2.0 which about sea cruises' experiences with people who love amazing sea cruises. The website will offer most of web 2.0 features.netcached - memcached client for .NET: netcached is a lightweight, high performance .NET client for memcached protocol.paipai: paipaiProjeto Zeus: PROJETO REALIZADO COMO TRABALHO ACADÊMICO.Roy's Tools: Roy's ToolsSuperCotka: SuperCotkaSzoftvertechnológia beadandó: Árva Balázs beadandójának projektvezeto oldalat az ELTE szoftvertechnológia tantárgyára.Twi.Fly: Twi.Fly is designed to change the way that you write most of your code.Coding likes flying, more than twice speed.Unicode IVS Add-in for Microsoft Office: "Unicode IVS Add-in for Microsoft Office" makes Microsoft Office 2007 and 2010 capable to load, save and edit documents contains Unicode IVS.Uyghur Named Date: Generate Uyghur named date string. ???????? ??? ?????? ????? ????? ?????Windows 8 Camp BH: Projeto contendo conteudo de ajuda para o Windows 8 Camp oferecido pelo Microsoft Inovation Center de Belo Horizonte.???????: ??wpf??????? ?? ??

  Read the article

• quick look at: dm_db_index_physical_stats

  - by fatherjack

  A quick look at the key data from this dmv that can help a DBA keep databases performing well and systems online as the users need them. When the dynamic management views relating to index statistics became available in SQL Server 2005 there was much hype about how they can help a DBA keep their servers running in better health than ever before. This particular view gives an insight into the physical health of the indexes present in a database. Whether they are use or unused, complete or missing some columns is irrelevant, this is simply the physical stats of all indexes; disabled indexes are ignored however. In it’s simplest form this dmv can be executed as:   The results from executing this contain a record for every index in every database but some of the columns will be NULL. The first parameter is there so that you can specify which database you want to gather index details on, rather than scan every database. Simply specifying DB_ID() in place of the first NULL achieves this. In order to avoid the NULLS, or more accurately, in order to choose when to have the NULLS you need to specify a value for the last parameter. It takes one of 4 values – DEFAULT, ‘SAMPLED’, ‘LIMITED’ or ‘DETAILED’. If you execute the dmv with each of these values you can see some interesting details in the times taken to complete each step. DECLARE @Start DATETIME DECLARE @First DATETIME DECLARE @Second DATETIME DECLARE @Third DATETIME DECLARE @Finish DATETIME SET @Start = GETDATE() SELECT * FROM [sys].[dm_db_index_physical_stats](DB_ID(), NULL, NULL, NULL, DEFAULT) AS ddips SET @First = GETDATE() SELECT * FROM [sys].[dm_db_index_physical_stats](DB_ID(), NULL, NULL, NULL, 'SAMPLED') AS ddips SET @Second = GETDATE() SELECT * FROM [sys].[dm_db_index_physical_stats](DB_ID(), NULL, NULL, NULL, 'LIMITED') AS ddips SET @Third = GETDATE() SELECT * FROM [sys].[dm_db_index_physical_stats](DB_ID(), NULL, NULL, NULL, 'DETAILED') AS ddips SET @Finish = GETDATE() SELECT DATEDIFF(ms, @Start, @First) AS [DEFAULT] , DATEDIFF(ms, @First, @Second) AS [SAMPLED] , DATEDIFF(ms, @Second, @Third) AS [LIMITED] , DATEDIFF(ms, @Third, @Finish) AS [DETAILED] Running this code will give you 4 result sets; DEFAULT will have 12 columns full of data and then NULLS in the remainder. SAMPLED will have 21 columns full of data. LIMITED will have 12 columns of data and the NULLS in the remainder. DETAILED will have 21 columns full of data. So, from this we can deduce that the DEFAULT value (the same one that is also applied when you query the view using a NULL parameter) is the same as using LIMITED. Viewing the final result set has some details that are worth noting: Running queries against this view takes significantly longer when using the SAMPLED and DETAILED values in the last parameter. The duration of the query is directly related to the size of the database you are working in so be careful running this on big databases unless you have tried it on a test server first. Let’s look at the data we get back with the DEFAULT value first of all and then progress to the extra information later. We know that the first parameter that we supply has to be a database id and for the purposes of this blog we will be providing that value with the DB_ID function. We could just as easily put a fixed value in there or a function such as DB_ID (‘AnyDatabaseName’). The first columns we get back are database_id and object_id. These are pretty explanatory and we can wrap those in some code to make things a little easier to read: SELECT DB_NAME([ddips].[database_id]) AS [DatabaseName] , OBJECT_NAME([ddips].[object_id]) AS [TableName] … FROM [sys].[dm_db_index_physical_stats](DB_ID(), NULL, NULL, NULL, NULL) AS ddips  gives us   SELECT DB_NAME([ddips].[database_id]) AS [DatabaseName] , OBJECT_NAME([ddips].[object_id]) AS [TableName], [i].[name] AS [IndexName] , ….. FROM [sys].[dm_db_index_physical_stats](DB_ID(), NULL, NULL, NULL, NULL) AS ddips INNER JOIN [sys].[indexes] AS i ON [ddips].[index_id] = [i].[index_id] AND [ddips].[object_id] = [i].[object_id]     These handily tie in with the next parameters in the query on the dmv. If you specify an object_id and an index_id in these then you get results limited to either the table or the specific index. Once again we can place a  function in here to make it easier to work with a specific table. eg. SELECT * FROM [sys].[dm_db_index_physical_stats] (DB_ID(), OBJECT_ID(‘AdventureWorks2008.Person.Address’) , 1, NULL, NULL) AS ddips   Note: Despite me showing that functions can be placed directly in the parameters for this dmv, best practice recommends that functions are not used directly in the function as it is possible that they will fail to return a valid object ID. To be certain of not passing invalid values to this function, and therefore setting an automated process off on the wrong path, declare variables for the OBJECT_IDs and once they have been validated, use them in the function: DECLARE @db_id SMALLINT; DECLARE @object_id INT; SET @db_id = DB_ID(N’AdventureWorks_2008′); SET @object_id = OBJECT_ID(N’AdventureWorks_2008.Person.Address’); IF @db_id IS NULL BEGINPRINT N’Invalid database’; ENDELSE IF @object_id IS NULL BEGINPRINT N’Invalid object’; ENDELSE BEGINSELECT * FROM sys.dm_db_index_physical_stats (@db_id, @object_id, NULL, NULL , ‘LIMITED’); END; GO In cases where the results of querying this dmv don’t have any effect on other processes (i.e. simply viewing the results in the SSMS results area)  then it will be noticed when the results are not consistent with the expected results and in the case of this blog this is the method I have used. So, now we can relate the values in these columns to something that we recognise in the database lets see what those other values in the dmv are all about. The next columns are: We’ll skip partition_number, index_type_desc, alloc_unit_type_desc, index_depth and index_level  as this is a quick look at the dmv and they are pretty self explanatory. The final columns revealed by querying this view in the DEFAULT mode are avg_fragmentation_in_percent. This is the amount that the index is logically fragmented. It will show NULL when the dmv is queried in SAMPLED mode. fragment_count. The number of pieces that the index is broken into. It will show NULL when the dmv is queried in SAMPLED mode. avg_fragment_size_in_pages. The average size, in pages, of a single fragment in the leaf level of the IN_ROW_DATA allocation unit. It will show NULL when the dmv is queried in SAMPLED mode. page_count. Total number of index or data pages in use. OK, so what does this give us? Well, there is an obvious correlation between fragment_count, page_count and avg_fragment_size-in_pages. We see that an index that takes up 27 pages and is in 3 fragments has an average fragment size of 9 pages (27/3=9). This means that for this index there are 3 separate places on the hard disk that SQL Server needs to locate and access to gather the data when it is requested by a DML query. If this index was bigger than 72KB then having it’s data in 3 pieces might not be too big an issue as each piece would have a significant piece of data to read and the speed of access would not be too poor. If the number of fragments increases then obviously the amount of data in each piece decreases and that means the amount of work for the disks to do in order to retrieve the data to satisfy the query increases and this would start to decrease performance. This information can be useful to keep in mind when considering the value in the avg_fragmentation_in_percent column. This is arrived at by an internal algorithm that gives a value to the logical fragmentation of the index taking into account the multiple files, type of allocation unit and the previously mentioned characteristics if index size (page_count) and fragment_count. Seeing an index with a high avg_fragmentation_in_percent value will be a call to action for a DBA that is investigating performance issues. It is possible that tables will have indexes that suffer from rapid increases in fragmentation as part of normal daily business and that regular defragmentation work will be needed to keep it in good order. In other cases indexes will rarely become fragmented and therefore not need rebuilding from one end of the year to another. Keeping this in mind DBAs need to use an ‘intelligent’ process that assesses key characteristics of an index and decides on the best, if any, defragmentation method to apply should be used. There is a simple example of this in the sample code found in the Books OnLine content for this dmv, in example D. There are also a couple of very popular solutions created by SQL Server MVPs Michelle Ufford and Ola Hallengren which I would wholly recommend that you review for much further detail on how to care for your SQL Server indexes. Right, let’s get back on track then. Querying the dmv with the fifth parameter value as ‘DETAILED’ takes longer because it goes through the index and refreshes all data from every level of the index. As this blog is only a quick look a we are going to skate right past ghost_record_count and version_ghost_record_count and discuss avg_page_space_used_in_percent, record_count, min_record_size_in_bytes, max_record_size_in_bytes and avg_record_size_in_bytes. We can see from the details below that there is a correlation between the columns marked. Column 1 (Page_Count) is the number of 8KB pages used by the index, column 2 is how full each page is (how much of the 8KB has actual data written on it), column 3 is how many records are recorded in the index and column 4 is the average size of each record. This approximates to: ((Col1*8) * 1024*(Col2/100))/Col3 = Col4*. avg_page_space_used_in_percent is an important column to review as this indicates how much of the disk that has been given over to the storage of the index actually has data on it. This value is affected by the value given for the FILL_FACTOR parameter when creating an index. avg_record_size_in_bytes is important as you can use it to get an idea of how many records are in each page and therefore in each fragment, thus reinforcing how important it is to keep fragmentation under control. min_record_size_in_bytes and max_record_size_in_bytes are exactly as their names set them out to be. A detail of the smallest and largest records in the index. Purely offered as a guide to the DBA to better understand the storage practices taking place. So, keeping an eye on avg_fragmentation_in_percent will ensure that your indexes are helping data access processes take place as efficiently as possible. Where fragmentation recurs frequently then potentially the DBA should consider; the fill_factor of the index in order to leave space at the leaf level so that new records can be inserted without causing fragmentation so rapidly. the columns used in the index should be analysed to avoid new records needing to be inserted in the middle of the index but rather always be added to the end. * – it’s approximate as there are many factors associated with things like the type of data and other database settings that affect this slightly.  Another great resource for working with SQL Server DMVs is Performance Tuning with SQL Server Dynamic Management Views by Louis Davidson and Tim Ford – a free ebook or paperback from Simple Talk. Disclaimer – Jonathan is a Friend of Red Gate and as such, whenever they are discussed, will have a generally positive disposition towards Red Gate tools. Other tools are often available and you should always try others before you come back and buy the Red Gate ones. All code in this blog is provided “as is” and no guarantee, warranty or accuracy is applicable or inferred, run the code on a test server and be sure to understand it before you run it on a server that means a lot to you or your manager.

  Read the article

• python: what are efficient techniques to deal with deeply nested data in a flexible manner?

  - by AlexandreS

  My question is not about a specific code snippet but more general, so please bear with me: How should I organize the data I'm analyzing, and which tools should I use to manage it? I'm using python and numpy to analyse data. Because the python documentation indicates that dictionaries are very optimized in python, and also due to the fact that the data itself is very structured, I stored it in a deeply nested dictionary. Here is a skeleton of the dictionary: the position in the hierarchy defines the nature of the element, and each new line defines the contents of a key in the precedent level: [AS091209M02] [AS091209M01] [AS090901M06] ... [100113] [100211] [100128] [100121] [R16] [R17] [R03] [R15] [R05] [R04] [R07] ... [1263399103] ... [ImageSize] [FilePath] [Trials] [Depth] [Frames] [Responses] ... [N01] [N04] ... [Sequential] [Randomized] [Ch1] [Ch2] Edit: To explain a bit better my data set: [individual] ex: [AS091209M02] [imaging session (date string)] ex: [100113] [Region imaged] ex: [R16] [timestamp of file] ex [1263399103] [properties of file] ex: [Responses] [regions of interest in image ] ex [N01] [format of data] ex [Sequential] [channel of acquisition: this key indexes an array of values] ex [Ch1] The type of operations I perform is for instance to compute properties of the arrays (listed under Ch1, Ch2), pick up arrays to make a new collection, for instance analyze responses of N01 from region 16 (R16) of a given individual at different time points, etc. This structure works well for me and is very fast, as promised. I can analyze the full data set pretty quickly (and the dictionary is far too small to fill up my computer's ram : half a gig). My problem comes from the cumbersome manner in which I need to program the operations of the dictionary. I often have stretches of code that go like this: for mk in dic.keys(): for rgk in dic[mk].keys(): for nk in dic[mk][rgk].keys(): for ik in dic[mk][rgk][nk].keys(): for ek in dic[mk][rgk][nk][ik].keys(): #do something which is ugly, cumbersome, non reusable, and brittle (need to recode it for any variant of the dictionary). I tried using recursive functions, but apart from the simplest applications, I ran into some very nasty bugs and bizarre behaviors that caused a big waste of time (it does not help that I don't manage to debug with pdb in ipython when I'm dealing with deeply nested recursive functions). In the end the only recursive function I use regularly is the following: def dicExplorer(dic, depth = -1, stp = 0): '''prints the hierarchy of a dictionary. if depth not specified, will explore all the dictionary ''' if depth - stp == 0: return try : list_keys = dic.keys() except AttributeError: return stp += 1 for key in list_keys: else: print '+%s> [\'%s\']' %(stp * '---', key) dicExplorer(dic[key], depth, stp) I know I'm doing this wrong, because my code is long, noodly and non-reusable. I need to either use better techniques to flexibly manipulate the dictionaries, or to put the data in some database format (sqlite?). My problem is that since I'm (badly) self-taught in regards to programming, I lack practical experience and background knowledge to appreciate the options available. I'm ready to learn new tools (SQL, object oriented programming), whatever it takes to get the job done, but I am reluctant to invest my time and efforts into something that will be a dead end for my needs. So what are your suggestions to tackle this issue, and be able to code my tools in a more brief, flexible and re-usable manner?

  Read the article

< Previous Page | 39 40 41 42 43 44 45  | Next Page >