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  • Profiling Startup Of VS2012 &ndash; YourKit Profiler

    - by Alois Kraus
    The YourKit (v7.0.5) profiler is interesting in terms of price (79€ single place license, 409€ + 1 year support and upgrades) and feature set. You do get a performance and memory profiler in one package for which you normally need also to pay extra from the other vendors. As an interesting side note the profiler UI is written in Java because they do also sell Java profilers with the same feature set. To get all methods of a VS startup you need first to configure it to include System* in the profiled methods and you need to configure * to measure wall clock time. By default it does record only CPU times which allows you to optimize CPU hungry operations. But you will never see a Thread.Sleep(10000) in the profiler blocking the UI in this mode. It can profile as all others processes started from within the profiler but it can also profile the next or all started processes. As usual it can profile in sampling and tracing mode. But since it is a memory profiler as well it does by default also record all object allocations > 1MB. With allocation recording enabled VS2012 did crash but without allocation recording there were no problems. The CPU tab contains the time line of the application and when you click in the graph you the call stacks of all threads at this time. This is really a nice feature. When you select a time region you the CPU Usage estimation for this time window. I have seen many applications consuming 100% CPU only because they did create garbage like crazy. For this is the Garbage Collection tab interesting in conjunction with a time range. This view is like the CPU table only that the CPU graph (green) is missing. All relevant information except for GCs/s is already visible in the CPU tab. Very handy to pinpoint excessive GC or CPU bound issues. The Threads tab does show the thread names and their lifetime. This is useful to see thread interactions or which thread is hottest in terms of CPU consumption. On the CPU tab the call tree does exist in a merged and thread specific view. When you click on a method you get below a list of all called methods. There you can sort for methods with a high own time which are worth optimizing. In the Method List you can select which scope you want to see. Back Traces are the methods which did call you. Callees ist the list of methods called directly or indirectly by your method as a flat list. This is not a call stack but still very useful to see which methods were slow so you can see the “root” cause quite quickly without the need to click trough long call stacks. The last view Merged Calles is a call stacked view of the previous view. This does help a lot to understand did call each method at run time. You would get the same view with a debugger for one call invocation but here you get the full statistics (invocation count) as well. Since YourKit is also a memory profiler you can directly see which objects you have on your managed heap and which objects do hold most of your precious memory. You can in in the Object Explorer view also examine the contents of your objects (strings or whatsoever) to get a better understanding which objects where potentially allocating this stuff.   YourKit is a very easy to use combined memory and performance profiler in one product. The unbeatable single license price makes it very attractive to straightly buy it. Although it is a Java UI it is very responsive and the memory consumption is considerably lower compared to dotTrace and ANTS profiler. What I do really like is to start the YourKit ui and then start the processes I want to profile as usual. There is no need to alter your own application code to be able to inject a profiler into your new started processes. For performance and memory profiling you can simply select the process you want to investigate from the list of started processes. That's the way I like to use profilers. Just get out of the way and let the application run without any special preparations.   Next: Telerik JustTrace

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  • Access Control Service v2: Registering Web Identities in your Applications [concepts]

    - by Your DisplayName here!
    ACS v2 support two fundamental types of client identities– I like to call them “enterprise identities” (WS-*) and “web identities” (Google, LiveID, OpenId in general…). I also see two different “mind sets” when it comes to application design using the above identity types: Enterprise identities – often the fact that a client can present a token from a trusted identity provider means he is a legitimate user of the application. Trust relationships and authorization details have been negotiated out of band (often on paper). Web identities – the fact that a user can authenticate with Google et al does not necessarily mean he is a legitimate (or registered) user of an application. Typically additional steps are necessary (like filling out a form, email confirmation etc). Sometimes also a mixture of both approaches exist, for the sake of this post, I will focus on the web identity case. I got a number of questions how to implement the web identity scenario and after some conversations it turns out it is the old authentication vs. authorization problem that gets in the way. Many people use the IsAuthenticated property on IIdentity to make security decisions in their applications (or deny user=”?” in ASP.NET terms). That’s a very natural thing to do, because authentication was done inside the application and we knew exactly when the IsAuthenticated condition is true. Been there, done that. Guilty ;) The fundamental difference between these “old style” apps and federation is, that authentication is not done by the application anymore. It is done by a third party service, and in the case of web identity providers, in services that are not under our control (nor do we have a formal business relationship with these providers). Now the issue is, when you switch to ACS, and someone with a Google account authenticates, indeed IsAuthenticated is true – because that’s what he is! This does not mean, that he is also authorized to use the application. It just proves he was able to authenticate with Google. Now this obviously leads to confusion. How can we solve that? Easy answer: We have to deal with authentication and authorization separately. Job done ;) For many application types I see this general approach: Application uses ACS for authentication (maybe both enterprise and web identities, we focus on web identities but you could easily have a dual approach here) Application offers to authenticate (or sign in) via web identity accounts like LiveID, Google, Facebook etc. Application also maintains a database of its “own” users. Typically you want to store additional information about the user In such an application type it is important to have a unique identifier for your users (think the primary key of your user database). What would that be? Most web identity provider (and all the standard ACS v2 supported ones) emit a NameIdentifier claim. This is a stable ID for the client (scoped to the relying party – more on that later). Furthermore ACS emits a claims identifying the identity provider (like the original issuer concept in WIF). When you combine these two values together, you can be sure to have a unique identifier for the user, e.g.: Facebook-134952459903700\799880347 You can now check on incoming calls, if the user is already registered and if yes, swap the ACS claims with claims coming from your user database. One claims would maybe be a role like “Registered User” which can then be easily used to do authorization checks in the application. The WIF claims authentication manager is a perfect place to do the claims transformation. If the user is not registered, show a register form. Maybe you can use some claims from the identity provider to pre-fill form fields. (see here where I show how to use the Facebook API to fetch additional user properties). After successful registration (which may include other mechanisms like a confirmation email), flip the bit in your database to make the web identity a registered user. This is all very theoretical. In the next post I will show some code and provide a download link for the complete sample. More on NameIdentifier Identity providers “guarantee” that the name identifier for a given user in your application will always be the same. But different applications (in the case of ACS – different ACS namespaces) will see different name identifiers. This is by design to protect the privacy of users because identical name identifiers could be used to create “profiles” of some sort for that user. In technical terms they create the name identifier approximately like this: name identifier = Hash((Provider Internal User ID) + (Relying Party Address)) Why is this important to know? Well – when you change the name of your ACS namespace, the name identifiers will change as well and you will will lose your “connection” to your existing users. Oh an btw – never use any other claims (like email address or name) to form a unique ID – these can often be changed by users.

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  • What Counts For a DBA: Fitness

    - by Louis Davidson
    If you know me, you can probably guess that physical exercise is not really my thing. There was a time in my past when it a larger part of my life, but even then never in the same sort of passionate way as a number of our SQL friends.  For me, I find that mental exercise satisfies what I believe to be the same inner need that drives people to run farther than I like to drive on most Saturday mornings, and it is certainly just as addictive. Mental fitness shares many common traits with physical fitness, especially the need to attain it through repetitive training. I only wish that mental training burned off a bacon cheeseburger in the same manner as does jogging around a dewy park on Saturday morning. In physical training, there are at least two goals, the first of which is to be physically able to do a task. The second is to train the brain to perform the task without thinking too hard about it. No matter how long it has been since you last rode a bike, you will be almost certainly be able to hop on and start riding without thinking about the process of pedaling or balancing. If you’ve never ridden a bike, you could be a physics professor /Olympic athlete and still crash the first few times you try, even though you are as strong as an ox and your knowledge of the physics of bicycle riding makes the concept child’s play. For programming tasks, the process is very similar. As a DBA, you will come to know intuitively how to backup, optimize, and secure database systems. As a data programmer, you will work to instinctively use the clauses of Transact-SQL DML so that, when you need to group data three ways (and not four), you will know to use the GROUP BY clause with GROUPING SETS without resorting to a search engine.  You have the skill. Making it naturally then requires repetition and experience is the primary requirement, not just simply learning about a topic. The hardest part of being really good at something is this difference between knowledge and skill. I have recently taken several informative training classes with Kimball University on data warehousing and ETL. Now I have a lot more knowledge about designing data warehouses than before. I have also done a good bit of data warehouse designing of late and have started to improve to some level of proficiency with the theory. Yet, for all of this head knowledge, it is still a struggle to take what I have learned and apply it to the designs I am working on.  Data warehousing is still a task that is not yet deeply ingrained in my brain muscle memory. On the other hand, relational database design is something that no matter how much or how little I may get to do it, I am comfortable doing it. I have done it as a profession now for well over a decade, I teach classes on it, and I also have done (and continue to do) a lot of mental training beyond the work day. Sometimes the training is just basic education, some reading blogs and attending sessions at PASS events.  My best training comes from spending time working on other people’s design issues in forums (though not nearly as much as I would like to lately). Working through other people’s problems is a great way to exercise your brain on problems with which you’re not immediately familiar. The final bit of exercise I find useful for cultivating mental fitness for a data professional is also probably the nerdiest thing that I will ever suggest you do.  Akin to running in place, the idea is to work through designs in your head. I have designed more than one database system that would revolutionize grocery store operations, sales at my local Target store, the ordering process at Amazon, and ways to improve Disney World operations to get me through a line faster (some of which they are starting to implement without any of my help.) Never are the designs truly fleshed out, but enough to work through structures and processes.  On “paper”, I have designed database systems to catalog things as trivial as my Lego creations, rental car companies and my audio and video collections. Once I get the database designed mentally, sometimes I will create the database, add some data (often using Red-Gate’s Data Generator), and write a few queries to see if a concept was realistic, but I will rarely fully flesh out the database since I have no desire to do any user interface programming anymore.  The mental training allows me to keep in practice for when the time comes to do the work I love the most for real…even if I have been spending most of my work time lately building data warehouses.  If you are really strong of mind and body, perhaps you can mix a mental run with a physical run; though don’t run off of a cliff while contemplating how you might design a database to catalog the trees on a mountain…that would be contradictory to the purpose of both types of exercise.

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  • What Counts for a DBA: Humility

    - by drsql
    In football (the American sort, naturally,) there are a select group of players who really hope to never have their names called during the game. They are members of the offensive line, and their job is to protect other players so they can deliver the ball to the goal to score points. When you do hear their name called, it is usually because they made a mistake and the player that they were supposed to protect ended up flat on his back admiring the clouds in the sky instead of advancing towards the goal to scoring point. Even on the rare occasion their name is called for a good reason, it is usually because they were making up for a teammate who had made a mistake and they covered up for them. The role of offensive lineman is a very good analogy for the role of the admin DBA. As a DBA, you are called on to be barely visible and rarely heard, protecting the company data assets tenaciously, even though the enemies to our craft surround us on all sides:. Developers: Cries of ‘foul!’ often ensue when the DBA says that they want data integrity to be stringently enforced and that documentation is needed so they can support systems, mostly because every error occurrence in the enterprise will be initially blamed on the database and fall to the DBA to troubleshoot. Insisting too loudly may bring those cries of ‘foul’ that somewhat remind you of when your 2 year old daughter didn't want to go to bed. The result of this petulance is that the next "enemy" gets involved. Managers: The concerns that motivate DBAs to argue will not excite the kind of manager who gets his technical knowledge from a glossy magazine filled with buzzwords, charts, and pretty pictures. However, the other programmers in the organization will tickle the buzzword void with a stream of new-sounding ideas and technologies constantly, along with warnings that if we did care about data integrity and document things, the budget would explode! In contrast, the arguments for integrity of data and supportability tend to be about as exciting as watching grass grow, and far too many manager types seem to prefer to smoke it than watch it. Packaged Applications: The DBA is rarely given a chance to review a new application that is being demonstrated for the enterprise, and rarer still is the DBA that gets a veto of an application because the database it uses has clearly been created by an architect that won't read a data modeling book because he is already married. More often than not this leads to hours of work for the DBA trying to performance-tune a database with a menagerie of rules that must be followed to stay within the  application support agreement, such as no changing indexes on a third party schema even though there are 10 billion rows instead of the 10 thousand when the system was last optimized. Hardware Failures: Physical disks, networking devices, memory, and backup devices all come with a measure known as ‘mean time before failure’ and it is never listed in centuries or eons. More like years, and the term ‘mean’ indicates that half of the devices are expected to fail before that, which by my calendar means any hour of any day that it wants to fail it will. But the DBA sucks it up and does the task at hand with a humility that makes them nearly invisible to all but the most observant person in the organization. The best DBAs I know are so proactive in their relentless pursuit of perfection that they detect many of the bugs (which they seldom caused) in the system well before they become a problem. In the end the DBA gets noticed for one of same two reasons as the offensive lineman. You make a mistake, like dropping a critical production database that had never been backed up; or when a system crashes for any reason whatsoever and they are on the spot with troubleshooting and system restoration plans that have been well thought out, tested, and tested again. Not because there is any glory in it, but because it is what they do.   Note: The characteristics of the professions referred to in this blog are meant to be overstated stereotypes for humorous effect, and even some DBAs aren't quite this perfect. If you are reading this far and haven’t hand written a 10 page flaming comment about how you are a _______ and you aren’t like this, that is awesome. Not every situation applies to everyone, but if you have never worked with a bad packaged app, a magazine trained manager, programmers that aren’t team players, or hardware that occasionally failed, relax and go have a unicorn sandwich before you wake up.

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  • Take Two: Comparing JVMs on ARM/Linux

    - by user12608080
    Although the intent of the previous article, entitled Comparing JVMs on ARM/Linux, was to introduce and highlight the availability of the HotSpot server compiler (referred to as c2) for Java SE-Embedded ARM v7,  it seems, based on feedback, that everyone was more interested in the OpenJDK comparisons to Java SE-E.  In fact there were two main concerns: The fact that the previous article compared Java SE-E 7 against OpenJDK 6 might be construed as an unlevel playing field because version 7 is newer and therefore potentially more optimized. That the generic compiler settings chosen to build the OpenJDK implementations did not put those versions in a particularly favorable light. With those considerations in mind, we'll institute the following changes to this version of the benchmarking: In order to help alleviate an additional concern that there is some sort of benchmark bias, we'll use a different suite, called DaCapo.  Funded and supported by many prestigious organizations, DaCapo's aim is to benchmark real world applications.  Further information about DaCapo can be found at http://dacapobench.org. At the suggestion of Xerxes Ranby, who has been a great help through this entire exercise, a newer Linux distribution will be used to assure that the OpenJDK implementations were built with more optimal compiler settings.  The Linux distribution in this instance is Ubuntu 11.10 Oneiric Ocelot. Having experienced difficulties getting Ubuntu 11.10 to run on the original D2Plug ARMv7 platform, for these benchmarks, we'll switch to an embedded system that has a supported Ubuntu 11.10 release.  That platform is the Freescale i.MX53 Quick Start Board.  It has an ARMv7 Coretex-A8 processor running at 1GHz with 1GB RAM. We'll limit comparisons to 4 JVM implementations: Java SE-E 7 Update 2 c1 compiler (default) Java SE-E 6 Update 30 (c1 compiler is the only option) OpenJDK 6 IcedTea6 1.11pre 6b23~pre11-0ubuntu1.11.10.2 CACAO build 1.1.0pre2 OpenJDK 6 IcedTea6 1.11pre 6b23~pre11-0ubuntu1.11.10.2 JamVM build-1.6.0-devel Certain OpenJDK implementations were eliminated from this round of testing for the simple reason that their performance was not competitive.  The Java SE 7u2 c2 compiler was also removed because although quite respectable, it did not perform as well as the c1 compilers.  Recall that c2 works optimally in long-lived situations.  Many of these benchmarks completed in a relatively short period of time.  To get a feel for where c2 shines, take a look at the first chart in this blog. The first chart that follows includes performance of all benchmark runs on all platforms.  Later on we'll look more at individual tests.  In all runs, smaller means faster.  The DaCapo aficionado may notice that only 10 of the 14 DaCapo tests for this version were executed.  The reason for this is that these 10 tests represent the only ones successfully completed by all 4 JVMs.  Only the Java SE-E 6u30 could successfully run all of the tests.  Both OpenJDK instances not only failed to complete certain tests, but also experienced VM aborts too. One of the first observations that can be made between Java SE-E 6 and 7 is that, for all intents and purposes, they are on par with regards to performance.  While it is a fact that successive Java SE releases add additional optimizations, it is also true that Java SE 7 introduces additional complexity to the Java platform thus balancing out any potential performance gains at this point.  We are still early into Java SE 7.  We would expect further performance enhancements for Java SE-E 7 in future updates. In comparing Java SE-E to OpenJDK performance, among both OpenJDK VMs, Cacao results are respectable in 4 of the 10 tests.  The charts that follow show the individual results of those four tests.  Both Java SE-E versions do win every test and outperform Cacao in the range of 9% to 55%. For the remaining 6 tests, Java SE-E significantly outperforms Cacao in the range of 114% to 311% So it looks like OpenJDK results are mixed for this round of benchmarks.  In some cases, performance looks to have improved.  But in a majority of instances, OpenJDK still lags behind Java SE-Embedded considerably. Time to put on my asbestos suit.  Let the flames begin...

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  • Business Case for investing time developing Stubs and BizUnit Tests

    - by charlie.mott
    I was recently in a position where I had to justify why effort should be spent developing Stubbed Integration Tests for BizTalk solutions. These tests are usually developed using the BizUnit framework. I assumed that most seasoned BizTalk developers would consider this best practice. Even though Microsoft suggest use of BizUnit on MSDN, I've not found a single site listing the justifications for investing time writing stubs and BizUnit tests. Stubs Stubs should be developed to isolate your development team from external dependencies. This is described by Michael Stephenson here. Failing to do this can result in the following problems: In contract-first scenarios, the external system interface will have been defined.  But the interface may not have been setup or even developed yet for the BizTalk developers to work with. By the time you open the target location to see the data BizTalk has sent, it may have been swept away. If you are relying on the UI of the target system to see the data BizTalk has sent, what do you do if it fails to arrive? It may take time for the data to be processed or it may be scheduled to be processed later. Learning how to use the source\target systems and investigations into where things go wrong in these systems will slow down the BizTalk development effort. By the time the data is visible in a UI it may have undergone further transformations. In larger development teams working together, do you all use the same source and target instances. How do you know which data was created by whose tests? How do you know which event log error message are whose?  Another developer may have “cleaned up” your data. It is harder to write BizUnit tests that clean up the data\logs after each test run. What if your B2B partners' source or target system cannot support the sort of testing you want to do. They may not even have a development or test instance that you can work with. Their single test instance may be used by the SIT\UAT teams. There may be licencing costs of setting up an instances of the external system. The stubs I like to use are generic stubs that can accept\return any message type.  Usually I need to create one per protocol. They should be driven by BizUnit steps to: validates the data received; and select a response messages (or error response). Once built, they can be re-used for many integration tests and from project to project. I’m not saying that developers should never test against a real instance.  Every so often, you still need to connect to real developer or test instances of the source and target endpoints\services. The interface developers may ask you to send them some data to see if everything still works.  Or you might want some messages sent to BizTalk to get confidence that everything still works beyond BizTalk. Tests Automated “Stubbed Integration Tests” are usually built using the BizUnit framework. These facilitate testing of the entire integration process from source stub to target stub. It will ensure that all of the BizTalk components are configured together correctly to meet all the requirements. More fine grained unit testing of individual BizTalk components is still encouraged.  But BizUnit provides much the easiest way to test some components types (e.g. Orchestrations). Using BizUnit with the Behaviour Driven Development approach described by Mike Stephenson delivers the following benefits: source: http://biztalkbddsample.codeplex.com – Video 1. Requirements can be easily defined using Given/When/Then Requirements are close to the code so easier to manage as features and scenarios Requirements are defined in domain language The feature files can be used as part of the documentation The documentation is accurate to the build of code and can be published with a release The scenarios are effective to document the scenarios and are not over excessive The scenarios are maintained with the code There’s an abstraction between the intention and implementation of tests making them easier to understand The requirements drive the testing These same tests can also be used to drive load testing as described here. If you don't do this ... If you don't follow the above “Stubbed Integration Tests” approach, the developer will need to manually trigger the tests. This has the following risks: Developers are unlikely to check all the scenarios each time and all the expected conditions each time. After the developer leaves, these manual test steps may be lost. What test scenarios are there?  What test messages did they use for each scenario? There is no mechanism to prove adequate test coverage. A test team may attempt to automate integration test scenarios in a test environment through the triggering of tests from a source system UI. If this is a replacement for BizUnit tests, then this carries the following risks: It moves the tests downstream, so problems will be found later in the process. Testers may not check all the expected conditions within the BizTalk infrastructure such as: event logs, suspended messages, etc. These automated tests may also get in the way of manual tests run on these environments.

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  • ADF Business Components

    - by Arda Eralp
    ADF Business Components and JDeveloper simplify the development, delivery, and customization of business applications for the Java EE platform. With ADF Business Components, developers aren't required to write the application infrastructure code required by the typical Java EE application to: Connect to the database Retrieve data Lock database records Manage transactions   ADF Business Components addresses these tasks through its library of reusable software components and through the supporting design time facilities in JDeveloper. Most importantly, developers save time using ADF Business Components since the JDeveloper design time makes typical development tasks entirely declarative. In particular, JDeveloper supports declarative development with ADF Business Components to: Author and test business logic in components which automatically integrate with databases Reuse business logic through multiple SQL-based views of data, supporting different application tasks Access and update the views from browser, desktop, mobile, and web service clients Customize application functionality in layers without requiring modification of the delivered application The goal of ADF Business Components is to make the business services developer more productive.   ADF Business Components provides a foundation of Java classes that allow your business-tier application components to leverage the functionality provided in the following areas: Simplifying Data Access Design a data model for client displays, including only necessary data Include master-detail hierarchies of any complexity as part of the data model Implement end-user Query-by-Example data filtering without code Automatically coordinate data model changes with business services layer Automatically validate and save any changes to the database   Enforcing Business Domain Validation and Business Logic Declaratively enforce required fields, primary key uniqueness, data precision-scale, and foreign key references Easily capture and enforce both simple and complex business rules, programmatically or declaratively, with multilevel validation support Navigate relationships between business domain objects and enforce constraints related to compound components   Supporting Sophisticated UIs with Multipage Units of Work Automatically reflect changes made by business service application logic in the user interface Retrieve reference information from related tables, and automatically maintain the information when the user changes foreign-key values Simplify multistep web-based business transactions with automatic web-tier state management Handle images, video, sound, and documents without having to use code Synchronize pending data changes across multiple views of data Consistently apply prompts, tooltips, format masks, and error messages in any application Define custom metadata for any business components to support metadata-driven user interface or application functionality Add dynamic attributes at runtime to simplify per-row state management   Implementing High-Performance Service-Oriented Architecture Support highly functional web service interfaces for business integration without writing code Enforce best-practice interface-based programming style Simplify application security with automatic JAAS integration and audit maintenance "Write once, run anywhere": use the same business service as plain Java class, EJB session bean, or web service   Streamlining Application Customization Extend component functionality after delivery without modifying source code Globally substitute delivered components with extended ones without modifying the application   ADF Business Components implements the business service through the following set of cooperating components: Entity object An entity object represents a row in a database table and simplifies modifying its data by handling all data manipulation language (DML) operations for you. These are basically your 1 to 1 representation of a database table. Each table in the database will have 1 and only 1 EO. The EO contains the mapping between columns and attributes. EO's also contain the business logic and validation. These are you core data services. They are responsible for updating, inserting and deleting records. The Attributes tab displays the actual mapping between attributes and columns, the mapping has following fields: Name : contains the name of the attribute we expose in our data model. Type : defines the data type of the attribute in our application. Column : specifies the column to which we want to map the attribute with Column Type : contains the type of the column in the database   View object A view object represents a SQL query. You use the full power of the familiar SQL language to join, filter, sort, and aggregate data into exactly the shape required by the end-user task. The attributes in the View Objects are actually coming from the Entity Object. In the end the VO will generate a query but you basically build a VO by selecting which EO need to participate in the VO and which attributes of those EO you want to use. That's why you have the Entity Usage column so you can see the relation between VO and EO. In the query tab you can clearly see the query that will be generated for the VO. At this stage we don't need it and just use it for information purpose. In later stages we might use it. Application module An application module is the controller of your data layer. It is responsible for keeping hold of the transaction. It exposes the data model to the view layer. You expose the VO's through the Application Module. This is the abstraction of your data layer which you want to show to the outside word.It defines an updatable data model and top-level procedures and functions (called service methods) related to a logical unit of work related to an end-user task. While the base components handle all the common cases through built-in behavior, customization is always possible and the default behavior provided by the base components can be easily overridden or augmented. When you create EO's, a foreign key will be translated into an association in our model. It defines the type of relation and who is the master and child as well as how the visibility of the association looks like. A similar concept exists to identify relations between view objects. These are called view links. These are almost identical as association except that a view link is based upon attributes defined in the view object. It can also be based upon an association. Here's a short summary: Entity Objects: representations of tables Association: Relations between EO's. Representations of foreign keys View Objects: Logical model View Links: Relationships between view objects Application Model: interface to your application  

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  • CS, SE, HCI, Information Science, Please recommendation for further education of the former performing art manager seeking career in IT industries? [on hold]

    - by Baek Seungjoo
    IT specialists there J Thank you very much for your collective efforts here, and I got huge help reading your professional comments and advices on each questions I have searched so far! This time, I would like to ask for your practical advices or recommendation on what I am struggling on at this moment. I am currently seeking higher education for my career transition from performing art manager and director to “IT software and/or service development and management specialist”. However, as this field is quite new to me, and there are lots of different work positions, I have no idea which grad major I better pursue in order to get qualification. Of course I know this question could sounds wired as it is kind of personal choice. But my lack of understanding on how IT software companies work in general, your practical and experience-based advice will be great help to me, who spent more than two months of self-research on net. OK. Before my question, here is my plan and history, which are quite different from those currently in IT industry I think… 1) Target Firstly, get career transition into IT service or products companies and get experiences. Eventually, pursue IT entrepreneurship in combination with my arts and cultural production and business expertise. 2) Background Career: performing arts director and manager in theatre-based scale opera and musical Art education in youth BA in literature and Chinese studies (Art & Humanities) MA in Cultural & Creative Industries (Art & Humanities) – dissertation with focus on digital prosumption and the lived experience of the prosumer. (a qualitative research on the agents in the digital world) 2) Personally Huge interest in IT hardware and software, and their trend. Skills to build up, repair, tune PCs -of course this is no more than personal hobby, but shows my interests in this field. 4) Problem Encounter a question “So, what do you think you can contribute practically in this position”. This question turn me down everytime I go through job interviews, and I decided more education in the relevant area. Here are my questions. 1) In terms of work positions in IT software companies, I wonder if I can put the comparison of what “Artists” is to “Arts Manager or Director” is what “Developer” is to “Product Manager”. (Of course, this stereotypical division of Artist-Art Manager is out of sense because the domain overlaps to some extent, and is blurring at least in my field, and they are in different contexts, but just speaking easily.) Normally, artist comes with special arts educations, and they live in their own world of artistic inspiration and creation, and they feel alive in practice and on stages. Meanwhile, from the point of staging and managing productions, the role of art manager is critical as well. Our role cares how the production appeals to the audience in effective way, how to make profit and future sustainable management through that, how to set up future strategy in consideration of the external conditions such as political and social circumstances, audience trend and level, other production trends from on-going and historical perspectives, how and what the production make voice to the society from political, economic, humanitarian stances. So, we need keen eyes on economic, political, and societal environment, have to understand human-being and their desires, must know how to make presentation and attract investors, must have sense in managing and fighting over the limited financial resource, how to extend networking and so on. It is common that the two agents create productions in collaboration (normally not in that ideal way but in conflict and fight though J ). So, we need to know each other’s expertise to some extent, for better production. What are the work positions in IT software industries equivalent to the role of “art manager” in performing arts? From my view, considering developers come with special education in the world of computer science, software engineering, or others (self-education sometimes), and they express themselves with the arts of coding, computer languages on the black screen, and make sort of their artistic production online to the audience, I guess there might be someone who collaborate with developers in creating, managing, and launching IT services or products. 2) Which education among CS, SE, HCI, Information Science, is needed for those seeking such work position? Especially for person like me. (At this moment, Information Science has the highest possibility to get in, since I lack Calculus and Math in undergrad educaiton. But please let me know irrespective of this concern, I think there are ways to back it up if CS or SE education needed in my case) 3) Which field between Information Science and HCI can be more practical background regarding job hungting? And which of them have more demands in job market? AS I checked, HCI is more close to CS than IS in its focus of study area. Thank you very much for your patience reading such a long inquiry, and I appreciate to your efforts in advance. Have a nice day in this beautiful summer.

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  • University teaches DOS-style C++, how to deal with it

    - by gaidal
    Half a year ago I had a look at available programming educations. I chose this one because unlike most of the choices: The majority of the courses seemed to be about something concrete and useful; the languages used are C++ and Java which are platform-independent; later courses include developing for mobile devices and a course on Android development, which seemed modern and relevant. Now after two introductory courses we're just starting with C++, and my programming professor seems a bit weird. He's tested us on things like "why should you use constants" and "why are globals bad" in a kind of mechanical way, without much context, before teaching actual programming. His handouts use system("pause"), system("cls"), and getch() from some conio.h that seems ancient according to what I've read. I just did a task that was about printing the "ASCII letters from 32 to 255" (huh?), with an example picture showing a table with Windows' Extended ASCII - of course I got other results for 128-255 on my Arch Linux that uses Unicode, and this isn't mentioned at all. I don't know, it just doesn't seem right... As if he is teaching programming because he has to, perhaps? Should I bring such things up? Hmm. I was looking forward to learning from someone who really knows stuff, and in an academic, rigorous way, like SICP or something. Aren't professors in programming supposed to be like that? I studied math for a while and every teacher and assistant there were really precise about what they said, but this is my second programming teacher that is sort of disappointing. Oh well. Now, question: Is this what to expect from universities or Not OK, and how do I deal with it? I have never touched the language C++ (or C) until now, and am not the right person to jump up and say "This is So Wrong!", so if I google something and find 10 people who say "xxx is blasphemy", how do I skillfully communicate this? I do think it would be better for those classmates who are total beginners not to learn bad habits (such as these vibes of total ignorance of other platforms!) during the upcoming courses, but don't want to disrespect the teacher. I don't know if it's reasonable or just cocky to bring up things like "what about other platforms?" or "but what about this article or stackoverflow answer that I read that said..." for every assignment? Or, if he keeps ignoring non-Windows-programming, should I give up and focus on my own projects or somehow argue that this really isn't OK nowadays? Are there any programming teachers out there, what do you think? By the way these are web-based courses, all interaction between teachers and students takes place in a forum. EDIT: A few answers seem to be making some incorrect assumptions, so maybe I should add a few things. I have been doing programming for fun on and off for 10 years, am pretty comfortable in 3 languages and read programming blogs et c regularly. Also, I feel kind of done being a student, having a degree in another field. I just need another, relevant diploma to work as a programmer, so I'm going back for that. Studying computer science for 5 years is not for me anymore, even though I enjoy learning and solving problems in my free time. Second, let me highlight that I don't expect it to be like the industry at all, quite the contrary. I expect it to be academic, dry and unnecessarily correct. No, it's not just math. Every professor I have had in math, or Japanese (major) or Chinese (minor) have been very very academic, discussing subtle points for hours with passion. But the courses I'm taking now and a previous one in programming don't seem serious. They neither resemble industry NOR academia. That is the problem. And it's not because I can't learn programming anyway. Third, I don't necessarily want to learn C++ or Android development, and I know I could teach myself those and anything else if I wanted to. But I am going back to school anyway, and those platform-independent languages and mobile stuff made me think that maybe they're serious about teaching something relevant here. Seems like I got this wrong, but we'll see.

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  • Avoiding coupling

    - by Seralize
    It is also true that a system may become so coupled, where each class is dependent on other classes that depend on other classes, that it is no longer possible to make a change in one place without having a ripple effect and having to make subsequent changes in many places.[1] This is why using an interface or an abstract class can be valuable in any object-oriented software project. Quote from Wikipedia Starting from scratch I'm starting from scratch with a project that I recently finished because I found the code to be too tightly coupled and hard to refactor, even when using MVC. I will be using MVC on my new project aswell but want to try and avoid the pitfalls this time, hopefully with your help. Project summary My issue is that I really wish to keep the Controller as clean as possible, but it seems like I can't do this. The basic idea of the program is that the user picks wordlists which is sent to the game engine. It will pick random words from the lists until there are none left. Problem at hand My main problem is that the game will have 'modes', and need to check the input in different ways through a method called checkWord(), but exactly where to put this and how to abstract it properly is a challenge to me. I'm new to design patterns, so not sure whether there exist any might fit my problem. My own attempt at abstraction Here is what I've gotten so far after hours of 'refactoring' the design plans, and I know it's long, but it's the best I could do to try and give you an overview (Note: As this is the sketch, anything is subject to change, all help and advice is very welcome. Also note the marked coupling points): Wordlist class Wordlist { // Basic CRUD etc. here! // Other sample methods: public function wordlistCount($user_id) {} // Returns count of how many wordlists a user has public function getAll($user_id) {} // Returns all wordlists of a user } Word class Word { // Basic CRUD etc. here! // Other sample methods: public function wordCount($wordlist_id) {} // Returns count of words in a wordlist public function getAll($wordlist_id) {} // Returns all words from a wordlist public function getWordInfo($word_id) {} // Returns information about a word } Wordpicker class Wordpicker { // The class needs to know which words and wordlists to exclude protected $_used_words = array(); protected $_used_wordlists = array(); // Wordlists to pick words from protected $_wordlists = array(); /* Public Methods */ public function setWordlists($wordlists = array()) {} public function setUsedWords($used_words = array()) {} public function setUsedWordlists($used_wordlists = array()) {} public function getRandomWord() {} // COUPLING POINT! Will most likely need to communicate with both the Wordlist and Word classes /* Protected Methods */ protected function _checkAvailableWordlists() {} // COUPLING POINT! Might need to check if wordlists are deleted etc. protected function _checkAvailableWords() {} // COUPLING POINT! Method needs to get all words in a wordlist from the Word class } Game class Game { protected $_session_id; // The ID of a game session which gets stored in the database along with game details protected $_game_info = array(); // Game instantiation public function __construct($user_id) { if (! $this->_session_id = $this->_gameExists($user_id)) { // New game } else { // Resume game } } // This is the method I tried to make flexible by using abstract classes etc. // Does it even belong in this class at all? public function checkWord($answer, $native_word, $translation) {} // This method checks the answer against the native word / translation word, depending on game mode public function getGameInfo() {} // Returns information about a game session, or creates it if it does not exist public function deleteSession($session_id) {} // Deletes a game session from the database // Methods dealing with game session information protected function _gameExists($user_id) {} protected function _getProgress($session_id) {} protected function _updateProgress($game_info = array()) {} } The Game /* CONTROLLER */ /* "Guess the word" page */ // User input $game_type = $_POST['game_type']; // Chosen with radio buttons etc. $wordlists = $_POST['wordlists']; // Chosen with checkboxes etc. // Starts a new game or resumes one from the database $game = new Game($_SESSION['user_id']); $game_info = $game->getGameInfo(); // Instantiates a new Wordpicker $wordpicker = new Wordpicker(); $wordpicker->setWordlists((isset($game_info['wordlists'])) ? $game_info['wordlists'] : $wordlists); $wordpicker->setUsedWordlists((isset($game_info['used_wordlists'])) ? $game_info['used_wordlists'] : NULL); $wordpicker->setUsedWords((isset($game_info['used_words'])) ? $game_info['used_words'] : NULL); // Fetches an available word if (! $word_id = $wordpicker->getRandomWord()) { // No more words left - game over! $game->deleteSession($game_info['id']); redirect(); } else { // Presents word details to the user $word = new Word(); $word_info = $word->getWordInfo($word_id); } The Bit to Finish /* CONTROLLER */ /* "Check the answer" page */ // ?????????????????? ( http://pastebin.com/cc6MtLTR ) Make sure you toggle the 'Layout Width' to the right for a better view. Thanks in advance. Questions To which extent should objects be loosely coupled? If object A needs info from object B, how is it supposed to get this without losing too much cohesion? As suggested in the comments, models should hold all business logic. However, as objects should be independent, where to glue them together? Should the model contain some sort of "index" or "client" area which connects the dots? Edit: So basically what I should do for a start is to make a new model which I can more easily call with oneliners such as $model->doAction(); // Lots of code in here which uses classes! How about the method for checking words? Should it be it's own object? I'm not sure where I should put it as it's pretty much part of the 'game'. But on another hand, I could just leave out the 'abstraction and OOPness' and make it a method of the 'client model' which will be encapsulated from the controller anyway. Very unsure about this.

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  • Microsoft Sql Server 2008 R2 System Databases

    For a majority of software developers little time is spent understanding the inner workings of the database management systems (DBMS) they use to store data for their applications.  I personally place myself in this grouping. In my case, I have used various versions of Microsoft’s SQL Server (2000, 2005, and 2008 R2) and just recently learned how valuable they really are when I was preparing to deliver a lecture on "SQL Server 2008 R2, System Databases". Microsoft Sql Server 2008 R2 System DatabasesSo what are system databases in MS SQL Server, and why should I know them? Microsoft uses system databases to support the SQL Server DBMS, much like a developer uses config files or database tables to support an application. These system databases individually provide specific functionality that allows MS SQL Server to function. Name Database File Log File Master master.mdf mastlog.ldf Resource mssqlsystemresource.mdf mssqlsystemresource.ldf Model model.mdf modellog.ldf MSDB msdbdata.mdf msdblog.ldf Distribution distmdl.mdf distmdl.ldf TempDB tempdb.mdf templog.ldf Master DatabaseIf you have used MS SQL Server then you should recognize the Master database especially if you used the SQL Server Management Studio (SSMS) to connect to a user created database. MS SQL Server requires the Master database in order for DBMS to start due to the information that it stores. Examples of data stored in the Master database User Logins Linked Servers Configuration information Information on User Databases Resource DatabaseHonestly, until recently I never knew this database even existed until I started to research SQL Server system databases. The reason for this is due largely to the fact that the resource database is hidden to users. In fact, the database files are stored within the Binn folder instead of the standard MS SQL Server database folder path. This database contains all system objects that can be accessed by all other databases.  In short, this database contains all system views and store procedures that appear in all other user databases regarding system information. One of the many benefits to storing system views and store procedures in a single hidden database is the fact it improves upgrading a SQL Server database; not to mention that maintenance is decreased since only one code base has to be mainlined for all of the system views and procedures. Model DatabaseThe Model database as the name implies is the model for all new databases created by users. This allows for predefining default database objects for all new databases within a MS SQL Server instance. For example, if every database created by a user needs to have an “Audit” table when it is  created then defining the “Audit” table in the model will guarantees that the table will be located in every new database create after the model is altered. MSDB DatabaseThe MSDBdatabase is used by SQL Server Agent, SQL Server Database Mail, SQL Server Service Broker, along with SQL Server. The SQL Server Agent uses this database to store job configurations and SQL job schedules along with SQL Alerts, and Operators. In addition, this database also stores all SQL job parameters along with each job’s execution history.  Finally, this database is also used to store database backup and maintenance plans as well as details pertaining to SQL Log shipping if it is being used. Distribution DatabaseThe Distribution database is only used during replication and stores meta data and history information pertaining to the act of replication data. Furthermore, when transactional replication is used this database also stores information regarding each transaction. It is important to note that replication is not turned on by default in MS SQL Server and that the distribution database is hidden from SSMS. Tempdb DatabaseThe Tempdb as the name implies is used to store temporary data and data objects. Examples of this include temp tables and temp store procedures. It is important to note that when using this database all data and data objects are cleared from this database when SQL Server restarts. This database is also used by SQL Server when it is performing some internal operations. Typically, SQL Server uses this database for the purpose of large sort and index operations. Finally, this database is used to store row versions if row versioning or snapsot isolation transactions are being used by SQL Server. Additionally, I would love to hear from others about their experiences using system databases, tables, and objects in a real world environments.

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  • Microsoft Sql Server 2008 R2 System Databases

    For a majority of software developers little time is spent understanding the inner workings of the database management systems (DBMS) they use to store data for their applications.  I personally place myself in this grouping. In my case, I have used various versions of Microsoft’s SQL Server (2000, 2005, and 2008 R2) and just recently learned how valuable they really are when I was preparing to deliver a lecture on "SQL Server 2008 R2, System Databases". Microsoft Sql Server 2008 R2 System DatabasesSo what are system databases in MS SQL Server, and why should I know them? Microsoft uses system databases to support the SQL Server DBMS, much like a developer uses config files or database tables to support an application. These system databases individually provide specific functionality that allows MS SQL Server to function. Name Database File Log File Master master.mdf mastlog.ldf Resource mssqlsystemresource.mdf mssqlsystemresource.ldf Model model.mdf modellog.ldf MSDB msdbdata.mdf msdblog.ldf Distribution distmdl.mdf distmdl.ldf TempDB tempdb.mdf templog.ldf Master DatabaseIf you have used MS SQL Server then you should recognize the Master database especially if you used the SQL Server Management Studio (SSMS) to connect to a user created database. MS SQL Server requires the Master database in order for DBMS to start due to the information that it stores. Examples of data stored in the Master database User Logins Linked Servers Configuration information Information on User Databases Resource DatabaseHonestly, until recently I never knew this database even existed until I started to research SQL Server system databases. The reason for this is due largely to the fact that the resource database is hidden to users. In fact, the database files are stored within the Binn folder instead of the standard MS SQL Server database folder path. This database contains all system objects that can be accessed by all other databases.  In short, this database contains all system views and store procedures that appear in all other user databases regarding system information. One of the many benefits to storing system views and store procedures in a single hidden database is the fact it improves upgrading a SQL Server database; not to mention that maintenance is decreased since only one code base has to be mainlined for all of the system views and procedures. Model DatabaseThe Model database as the name implies is the model for all new databases created by users. This allows for predefining default database objects for all new databases within a MS SQL Server instance. For example, if every database created by a user needs to have an “Audit” table when it is  created then defining the “Audit” table in the model will guarantees that the table will be located in every new database create after the model is altered. MSDB DatabaseThe MSDBdatabase is used by SQL Server Agent, SQL Server Database Mail, SQL Server Service Broker, along with SQL Server. The SQL Server Agent uses this database to store job configurations and SQL job schedules along with SQL Alerts, and Operators. In addition, this database also stores all SQL job parameters along with each job’s execution history.  Finally, this database is also used to store database backup and maintenance plans as well as details pertaining to SQL Log shipping if it is being used. Distribution DatabaseThe Distribution database is only used during replication and stores meta data and history information pertaining to the act of replication data. Furthermore, when transactional replication is used this database also stores information regarding each transaction. It is important to note that replication is not turned on by default in MS SQL Server and that the distribution database is hidden from SSMS. Tempdb DatabaseThe Tempdb as the name implies is used to store temporary data and data objects. Examples of this include temp tables and temp store procedures. It is important to note that when using this database all data and data objects are cleared from this database when SQL Server restarts. This database is also used by SQL Server when it is performing some internal operations. Typically, SQL Server uses this database for the purpose of large sort and index operations. Finally, this database is used to store row versions if row versioning or snapsot isolation transactions are being used by SQL Server. Additionally, I would love to hear from others about their experiences using system databases, tables, and objects in a real world environments.

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  • Inside Red Gate - Be Reasonable!

    - by simonc
    As I discussed in my previous posts, divisions and project teams within Red Gate are allowed a lot of autonomy to manage themselves. It's not just the teams though, there's an awful lot of freedom given to individual employees within the company as well. Reasonableness How Red Gate treats it's employees is embodied in the phrase 'You will be reasonable with us, and we will be reasonable with you'. As an employee, you are trusted to do your job to the best of you ability. There's no one looking over your shoulder, no one clocking you in and out each day. Everyone is working at the company because they want to, and one of the core ideas of Red Gate is that the company exists to 'let people do the best work of their lives'. Everything is geared towards that. To help you do your job, office services and the IT department are there. If you need something to help you work better (a third or fourth monitor, footrests, or a new keyboard) then ask people in Information Systems (IS) or Office Services and you will be given it, no questions asked. Everyone has administrator access to their own machines, and you can install whatever you want on it. If there's a particular bit of software you need, then ask IS and they will buy it. As an example, last year I wanted to replace my main hard drive with an SSD; I had a summer job at school working in a computer repair shop, so knew what to do. I went to IS and asked for 'an SSD, a SATA cable, and a screwdriver'. And I got it there and then, even the screwdriver. Awesome. I screwed it in myself, copied all my main drive files across, and I was good to go. Of course, if you're not happy doing that yourself, then IS will sort it all out for you, no problems. If you need something that the company doesn't have (say, a book off Amazon, or you need some specifications printing off & bound), then everyone has a expense limit of £100 that you can use without any sign-off needed from your managers. If you need a company credit card for whatever reason, then you can get it. This freedom extends to working hours and holiday; you're expected to be in the office 11am-3pm each day, but outside those times you can work whenever you want. If you need a half-day holiday on a days notice, or even the same day, then you'll get it, unless there's a good reason you're needed that day. If you need to work from home for a day or so for whatever reason, then you can. If it's reasonable, then it's allowed. Trust issues? A lot of trust, and a lot of leeway, is given to all the people in Red Gate. Everyone is expected to work hard, do their jobs to the best of their ability, and there will be a minimum of bureaucratic obstacles that stop you doing your work. What happens if you abuse this trust? Well, an example is company trip expenses. You're free to expense what you like; food, drink, transport, etc, but if you expenses are not reasonable, then you will never travel with the company again. Simple as that. Everyone knows when they're abusing the system, so simply don't do it. Along with reasonableness, another phrase used is 'Don't be an a**hole'. If you act like an a**hole, and abuse any of the trust placed in you, even if you're the best tester, salesperson, dev, or manager in the company, then you won't be a part of the company any more. From what I know about other companies, employee trust is highly variable between companies, all the way up to CCTV trained on employee's monitors. As a dev, I want to produce well-written & useful code that solves people's problems. Being able to get whatever I need - install whatever tools I need, get time off when I need to, obtain reference books within a day - all let me do my job, and so let Red Gate help other people do their own jobs through the tools we produce. Plus, I don't think I would like working for a company that doesn't allow admin access to your own machine and blocks Facebook! Cross posted from Simple Talk.

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  • What to leave when you're leaving

    - by BuckWoody
    There's already a post on this topic - sort of. I read this entry, where the author did a good job on a few steps, but I found that a few other tips might be useful, so if you want to check that one out and then this post, you might be able to put together your own plan for when you leave your job.  I once took over the system administrator (of which the Oracle and SQL Server servers were a part) at a mid-sized firm. The outgoing administrator had about a two- week-long scheduled overlap with me, but was angry at the company and told me "hey, I know this is going to be hard on you, but I want them to know how important I was. I'm not telling you where anything is or what the passwords are. Good luck!" He then quit that day. It took me about three days to find all of the servers and crack the passwords. Yes, the company tried to take legal action against the guy and all that, but he moved back to his home country and so largely got away with it. Obviously, this isn't the way to leave a job. Many of us have changed jobs in the past, and most of us try to be very professional about the transition to a new team, regardless of the feelings about a particular company. I've been treated badly at a firm, but that is no reason to leave a mess for someone else. So here's what you should put into place at a minimum before you go. Most of this is common sense - which of course isn't very common these days - and another good rule is just to ask yourself "what would I want to know"? The article I referenced at the top of this post focuses on a lot of documentation of the systems. I think that's fine, but in actuality, I really don't need that. Even with this kind of documentation, I still perform a full audit on the systems, so in the end I create my own system documentation. There are actually only four big items I need to know to get started with the systems: 1. Where is everything/everybody?The first thing I need to know is where all of the systems are. I mean not only the street address, but the closet or room, the rack number, the IU number in the rack, the SAN luns, all that. A picture here is worth a thousand words, which is why I really like Visio. It combines nice graphics, full text and all that. But use whatever you have to tell someone the physical locations of the boxes. Also, tell them the physical location of the folks in charge of those boxes (in case you aren't) or who share that responsibility. And by "where" in this case, I mean names and phones.  2. What do they do?For both the servers and the people, tell them what they do. If it's a database server, detail what each database does and what application goes to that, and who "owns" that application. In my mind, this is one of hte most important things a Data Professional needs to know. In the case of the other administrtors or co-owners, document each person's responsibilities.   3. What are the credentials?Logging on/in and gaining access to the buildings are things that the new Data Professional will need to do to successfully complete their job. This means service accounts, certificates, all of that. The first thing they should do, of course, is change the passwords on all that, but the first thing they need is the ability to do that!  4. What is out of the ordinary?This is the most tricky, and perhaps the next most important thing to know. Did you have to use a "special" driver for that video card on server X? Is the person that co-owns an application with you mentally unstable (like me) or have special needs, like "don't talk to Buck before he's had coffee. Nothing will make any sense"? Do you have service pack requirements for a specific setup? Write all that down. Anything that took you a day or longer to make work is probably a candidate here. This is my short list - anything you care to add? Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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  • How can I implement a database TableView like thing in C++?

    - by Industrial-antidepressant
    How can I implement a TableView like thing in C++? I want to emulating a tiny relation database like thing in C++. I have data tables, and I want to transform it somehow, so I need a TableView like class. I want filtering, sorting, freely add and remove items and transforming (ex. view as UPPERCASE and so on). The whole thing is inside a GUI application, so datatables and views are attached to a GUI (or HTML or something). So how can I identify an item in the view? How can I signal it when the table is changed? Is there some design pattern for this? Here is a simple table, and a simple data item: #include <string> #include <boost/multi_index_container.hpp> #include <boost/multi_index/member.hpp> #include <boost/multi_index/ordered_index.hpp> #include <boost/multi_index/random_access_index.hpp> using boost::multi_index_container; using namespace boost::multi_index; struct Data { Data() {} int id; std::string name; }; struct row{}; struct id{}; struct name{}; typedef boost::multi_index_container< Data, indexed_by< random_access<tag<row> >, ordered_unique<tag<id>, member<Data, int, &Data::id> >, ordered_unique<tag<name>, member<Data, std::string, &Data::name> > > > TDataTable; class DataTable { public: typedef Data item_type; typedef TDataTable::value_type value_type; typedef TDataTable::const_reference const_reference; typedef TDataTable::index<row>::type TRowIndex; typedef TDataTable::index<id>::type TIdIndex; typedef TDataTable::index<name>::type TNameIndex; typedef TRowIndex::iterator iterator; DataTable() : row_index(rule_table.get<row>()), id_index(rule_table.get<id>()), name_index(rule_table.get<name>()), row_index_writeable(rule_table.get<row>()) { } TDataTable::const_reference operator[](TDataTable::size_type n) const { return rule_table[n]; } std::pair<iterator,bool> push_back(const value_type& x) { return row_index_writeable.push_back(x); } iterator erase(iterator position) { return row_index_writeable.erase(position); } bool replace(iterator position,const value_type& x) { return row_index_writeable.replace(position, x); } template<typename InputIterator> void rearrange(InputIterator first) { return row_index_writeable.rearrange(first); } void print_table() const; unsigned size() const { return row_index.size(); } TDataTable rule_table; const TRowIndex& row_index; const TIdIndex& id_index; const TNameIndex& name_index; private: TRowIndex& row_index_writeable; }; class DataTableView { DataTableView(const DataTable& source_table) {} // How can I implement this? // I want filtering, sorting, signaling upper GUI layer, and sorting, and ... }; int main() { Data data1; data1.id = 1; data1.name = "name1"; Data data2; data2.id = 2; data2.name = "name2"; DataTable table; table.push_back(data1); DataTable::iterator it1 = table.row_index.iterator_to(table[0]); table.erase(it1); table.push_back(data1); Data new_data(table[0]); new_data.name = "new_name"; table.replace(table.row_index.iterator_to(table[0]), new_data); for (unsigned i = 0; i < table.size(); ++i) std::cout << table[i].name << std::endl; #if 0 // using scenarios: DataTableView table_view(table); table_view.fill_from_source(); // synchronization with source table_view.remove(data_item1); // remove item from view table_view.add(data_item2); // add item from source table table_view.filter(filterfunc); // filtering table_view.sort(sortfunc); // sorting // modifying from source_able, hot to signal the table_view? // FYI: Table view is atteched to a GUI item table.erase(data); table.replace(data); #endif return 0; }

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  • Data Source Security Part 1

    - by Steve Felts
    I’ve written a couple of articles on how to store data source security credentials using the Oracle wallet.  I plan to write a few articles on the various types of security available to WebLogic Server (WLS) data sources.  There are more options than you might think! There have been several enhancements in this area in WLS 10.3.6.  There are a couple of more enhancements planned for release WLS 12.1.2 that I will include here for completeness.  This isn’t intended as a teaser.  If you call your Oracle support person, you can get them now as minor patches to WLS 10.3.6.   The current security documentation is scattered in a few places, has a few incorrect statements, and is missing a few topics.  It also seems that the knowledge of how to apply some of these features isn’t written down.  The goal of these articles is to talk about WLS data source security in a unified way and to introduce some approaches to using the available features.  Introduction to WebLogic Data Source Security Options By default, you define a single database user and password for a data source.  You can store it in the data source descriptor or make use of the Oracle wallet.  This is a very simple and efficient approach to security.  All of the connections in the connection pool are owned by this user and there is no special processing when a connection is given out.  That is, it’s a homogeneous connection pool and any request can get any connection from a security perspective (there are other aspects like affinity).  Regardless of the end user of the application, all connections in the pool use the same security credentials to access the DBMS.   No additional information is needed when you get a connection because it’s all available from the data source descriptor (or wallet). java.sql.Connection conn =  mydatasource.getConnection(); Note: You can enter the password as a name-value pair in the Properties field (this not permitted for production environments) or you can enter it in the Password field of the data source descriptor. The value in the Password field overrides any password value defined in the Properties passed to the JDBC Driver when creating physical database connections. It is recommended that you use the Password attribute in place of the password property in the properties string because the Password value is encrypted in the configuration file (stored as the password-encrypted attribute in the jdbc-driver-params tag in the module file) and is hidden in the administration console.  The Properties and Password fields are located on the administration console Data Source creation wizard or Data Source Configuration tab. The JDBC API can also be used to programmatically specify a database user name and password as in the following.  java.sql.Connection conn = mydatasource.getConnection(“user”, “password”); According to the JDBC specification, it’s supposed to take a database user and associated password but different vendors implement this differently.  WLS, by default, treats this as an application server user and password.  The pair is authenticated to see if it’s a valid user and that user is used for WLS security permission checks.  By default, the user is then mapped to a database user and password using the data source credential mapper, so this API sort of follows the specification but database credentials are one-step removed from the application code.  More details and the rationale are described later. While the default approach is simple, it does mean that only one database user is doing all of the work.  You can’t figure out who actually did the update and you can’t restrict SQL operations by who is running the operation, at least at the database level.   Any type of per-user logic will need to be in the application code instead of having the database do it.  There are various WLS data source features that can be configured to provide some per-user information about the operations to the database. WebLogic Data Source Security Options This table describes the features available for WebLogic data sources to configure database security credentials and a brief description.  It also captures information about the compatibility of these features with one another. Feature Description Can be used with Can’t be used with User authentication (default) Default getConnection(user, password) behavior – validate the input and use the user/password in the descriptor. Set client identifier Proxy Session, Identity pooling, Use database credentials Use database credentials Instead of using the credential mapper, use the supplied user and password directly. Set client identifier, Proxy session, Identity pooling User authentication, Multi Data Source Set Client Identifier Set a client identifier property associated with the connection (Oracle and DB2 only). Everything Proxy Session Set a light-weight proxy user associated with the connection (Oracle-only). Set client identifier, Use database credentials Identity pooling, User authentication Identity pooling Heterogeneous pool of connections owned by specified users. Set client identifier, Use database credentials Proxy session, User authentication, Labeling, Multi-datasource, Active GridLink Note that all of these features are available with both XA and non-XA drivers. Currently, the Proxy Session and Use Database Credentials options are on the Oracle tab of the Data Source Configuration tab of the administration console (even though the Use Database Credentials feature is not just for Oracle databases – oops).  The rest of the features are on the Identity tab of the Data Source Configuration tab in the administration console (plan on seeing them all in one place in the future). The subsequent articles will describe these features in more detail.  Keep referring back to this table to see the big picture.

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  • What Counts for A DBA: Observant

    - by drsql
    When walking up to the building where I work, I can see CCTV cameras placed here and there for monitoring access to the building. We are required to wear authorization badges which could be checked at any time. Do we have enemies?  Of course! No one is 100% safe; even if your life is a fairy tale, there is always a witch with an apple waiting to snack you into a thousand years of slumber (or at least so I recollect from elementary school.) Even Little Bo Peep had to keep a wary lookout.    We nerdy types (or maybe it was just me?) generally learned on the school playground to keep an eye open for unprovoked attack from simpler, but more muscular souls, and take steps to avoid messy confrontations well in advance. After we’d apprehensively negotiated adulthood with varying degrees of success, these skills of watching for danger, and avoiding it,  translated quite well to the technical careers so many of us were destined for. And nowhere else is this talent for watching out for irrational malevolence so appropriate as in a career as a production DBA.   It isn’t always active malevolence that the DBA needs to watch out for, but the even scarier quirks of common humanity.  A large number of the issues that occur in the enterprise happen just randomly or even just one time ever in a spurious manner, like in the case where a person decided to download the entire MSDN library of software, cross join every non-indexed billion row table together, and simultaneously stream the HD feed of 5 different sporting events, making the network access slow while the corporate online sales just started. The decent DBA team, like the going, gets tough under such circumstances. They spring into action, checking all of the sources of active information, observes the issue is no longer happening now, figures that either it wasn’t the database’s fault and that the reboot of the whatever device on the network fixed the problem.  This sort of reactive support is good, and will be the initial reaction of even excellent DBAs, but it is not the end of the story if you really want to know what happened and avoid getting called again when it isn’t even your fault.   When fires start raging within the corporate software forest, the DBA’s instinct is to actively find a way to douse the flames and get back to having no one in the company have any idea who they are.  Even better for them is to find a way of killing a potential problem while the fires are small, long before they can be classified as raging. The observant DBA will have already been monitoring the server environment for months in advance.  Most troubles, such as disk space and security intrusions, can be predicted and dealt with by alerting systems, whereas other trouble can come out of the blue and requires a skill of observing ongoing conditions and noticing inexplicable changes that could signal an emerging problem.  You can’t automate the DBA, because the bankable skill of a DBA is in detecting the early signs of unexpected problems, and working out how to deal with them before anyone else notices them.    To achieve this, the DBA will check the situation as it is currently happening,  and in many cases is likely to have been the person who submitted the problem to the level 1 support person in the first place, just to let the support team know of impending issues (always well received, I tell you what!). Database and host computer settings, configurations, and even critical data might be profiled and captured for later comparisons. He’ll use Monitoring tools, built-in, commercial (Not to be too crassly commercial or anything, but there is one such tool is SQL Monitor) and lots of homebrew monitoring tools to monitor for problems and changes in the server environment.   You will know that you have it right when a support call comes in and you can look at your monitoring tools and quickly respond that “response time is well within the normal range, the query that supports the failing interface works perfectly and has actually only been called 67% as often as normal, so I am more than willing to help diagnose the problem, but it isn’t the database server’s fault and is probably a client or networking slowdown causing the interface to be used less frequently than normal.” And that is the best thing for any DBA to observe…

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  • How can I estimate the entropy of a password?

    - by Wug
    Having read various resources about password strength I'm trying to create an algorithm that will provide a rough estimation of how much entropy a password has. I'm trying to create an algorithm that's as comprehensive as possible. At this point I only have pseudocode, but the algorithm covers the following: password length repeated characters patterns (logical) different character spaces (LC, UC, Numeric, Special, Extended) dictionary attacks It does NOT cover the following, and SHOULD cover it WELL (though not perfectly): ordering (passwords can be strictly ordered by output of this algorithm) patterns (spatial) Can anyone provide some insight on what this algorithm might be weak to? Specifically, can anyone think of situations where feeding a password to the algorithm would OVERESTIMATE its strength? Underestimations are less of an issue. The algorithm: // the password to test password = ? length = length(password) // unique character counts from password (duplicates discarded) uqlca = number of unique lowercase alphabetic characters in password uquca = number of uppercase alphabetic characters uqd = number of unique digits uqsp = number of unique special characters (anything with a key on the keyboard) uqxc = number of unique special special characters (alt codes, extended-ascii stuff) // algorithm parameters, total sizes of alphabet spaces Nlca = total possible number of lowercase letters (26) Nuca = total uppercase letters (26) Nd = total digits (10) Nsp = total special characters (32 or something) Nxc = total extended ascii characters that dont fit into other categorys (idk, 50?) // algorithm parameters, pw strength growth rates as percentages (per character) flca = entropy growth factor for lowercase letters (.25 is probably a good value) fuca = EGF for uppercase letters (.4 is probably good) fd = EGF for digits (.4 is probably good) fsp = EGF for special chars (.5 is probably good) fxc = EGF for extended ascii chars (.75 is probably good) // repetition factors. few unique letters == low factor, many unique == high rflca = (1 - (1 - flca) ^ uqlca) rfuca = (1 - (1 - fuca) ^ uquca) rfd = (1 - (1 - fd ) ^ uqd ) rfsp = (1 - (1 - fsp ) ^ uqsp ) rfxc = (1 - (1 - fxc ) ^ uqxc ) // digit strengths strength = ( rflca * Nlca + rfuca * Nuca + rfd * Nd + rfsp * Nsp + rfxc * Nxc ) ^ length entropybits = log_base_2(strength) A few inputs and their desired and actual entropy_bits outputs: INPUT DESIRED ACTUAL aaa very pathetic 8.1 aaaaaaaaa pathetic 24.7 abcdefghi weak 31.2 H0ley$Mol3y_ strong 72.2 s^fU¬5ü;y34G< wtf 88.9 [a^36]* pathetic 97.2 [a^20]A[a^15]* strong 146.8 xkcd1** medium 79.3 xkcd2** wtf 160.5 * these 2 passwords use shortened notation, where [a^N] expands to N a's. ** xkcd1 = "Tr0ub4dor&3", xkcd2 = "correct horse battery staple" The algorithm does realize (correctly) that increasing the alphabet size (even by one digit) vastly strengthens long passwords, as shown by the difference in entropy_bits for the 6th and 7th passwords, which both consist of 36 a's, but the second's 21st a is capitalized. However, they do not account for the fact that having a password of 36 a's is not a good idea, it's easily broken with a weak password cracker (and anyone who watches you type it will see it) and the algorithm doesn't reflect that. It does, however, reflect the fact that xkcd1 is a weak password compared to xkcd2, despite having greater complexity density (is this even a thing?). How can I improve this algorithm? Addendum 1 Dictionary attacks and pattern based attacks seem to be the big thing, so I'll take a stab at addressing those. I could perform a comprehensive search through the password for words from a word list and replace words with tokens unique to the words they represent. Word-tokens would then be treated as characters and have their own weight system, and would add their own weights to the password. I'd need a few new algorithm parameters (I'll call them lw, Nw ~= 2^11, fw ~= .5, and rfw) and I'd factor the weight into the password as I would any of the other weights. This word search could be specially modified to match both lowercase and uppercase letters as well as common character substitutions, like that of E with 3. If I didn't add extra weight to such matched words, the algorithm would underestimate their strength by a bit or two per word, which is OK. Otherwise, a general rule would be, for each non-perfect character match, give the word a bonus bit. I could then perform simple pattern checks, such as searches for runs of repeated characters and derivative tests (take the difference between each character), which would identify patterns such as 'aaaaa' and '12345', and replace each detected pattern with a pattern token, unique to the pattern and length. The algorithmic parameters (specifically, entropy per pattern) could be generated on the fly based on the pattern. At this point, I'd take the length of the password. Each word token and pattern token would count as one character; each token would replace the characters they symbolically represented. I made up some sort of pattern notation, but it includes the pattern length l, the pattern order o, and the base element b. This information could be used to compute some arbitrary weight for each pattern. I'd do something better in actual code. Modified Example: Password: 1234kitty$$$$$herpderp Tokenized: 1 2 3 4 k i t t y $ $ $ $ $ h e r p d e r p Words Filtered: 1 2 3 4 @W5783 $ $ $ $ $ @W9001 @W9002 Patterns Filtered: @P[l=4,o=1,b='1'] @W5783 @P[l=5,o=0,b='$'] @W9001 @W9002 Breakdown: 3 small, unique words and 2 patterns Entropy: about 45 bits, as per modified algorithm Password: correcthorsebatterystaple Tokenized: c o r r e c t h o r s e b a t t e r y s t a p l e Words Filtered: @W6783 @W7923 @W1535 @W2285 Breakdown: 4 small, unique words and no patterns Entropy: 43 bits, as per modified algorithm The exact semantics of how entropy is calculated from patterns is up for discussion. I was thinking something like: entropy(b) * l * (o + 1) // o will be either zero or one The modified algorithm would find flaws with and reduce the strength of each password in the original table, with the exception of s^fU¬5ü;y34G<, which contains no words or patterns.

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  • How do I dig myself out of this DEEP hole? [closed]

    - by user74847
    I may be a bit bias in the way i word this but any opinions and suggestions are welcome. I should start by saying i have a MSc in CS and a degree in new media +6 years expereince and im probably around a middleweight developer. I started a web development company with my friend from uni a year ago, there was a 4 month gap in the middle where i went miles away work on a big project. Ive since returned and picked up where we left off. A year on though i find im still staying up til 5am and getting up at 9 sometimes 2-3 days without sleep. While i was away i was working 9-5 and struggling to keep up with doing stuff for my clients 8 hours ahead, after work, so things stagnated. We currently have about 12 active projects, with one other part time developer and a full time freelancer who is dealing with one of our major projects. I am solely responsible for concurrently developing 2 big sites similar to gumtree in functionality, at the same time as about 5-6+ small WordPress based 5-10page sites. a lot of the content isnt in yet or the client is delaying so i chop and change project every other day which does my head in. Is it reasonable to expect myself to remember the intricate details of each project when i come back to it a week later? and remember the details of a task which hasnt been written down? my business partner seems to think so. or am i just forgetful? Im particularly bad at estimating timescales which doesnt help, added to that a lot of the technologies im am using are new to me (a magento site took weeks to theme rather than days and was full of bugs, even after 1000's of google searches and hours reading forums) im still trying to learn and find the best CMS for us to use and getting my head around the likes of Bootstrap and jquery, Cpanel / Linux (we just got a blank vps for me to set up with no experience) even installing an SSL certificate caused everyone's mail clients to go down which was more stress for me to sort out. I find the pressure of the workload and timescales and trying to learn this stuff so fast is beginning to turn me against my career path. The fact that i never seem to get anything done really winds up my business partner and iv come to associate him with the stress and pain of the whole situation especially when I get berated or a look that says "oh you retard" when I forget something. Even today i spent hours learning how a particular themeforest theme worked with wordpress and how i could twist it to work for our partiuclar needs, on the surface had done no work, that triggered a 30 minute tirade of anger and stress and questioning what i had done from my business partner. had i taken too long to work on that? shoudl i have done it in 2 hours instead of 6? i told him i would take 2 hours. i was wrong. I feel like im running myself into the ground. My sleeping pattern has got so bad that when im working im half asleep and making mistakes, my eyes are constantly purple underneath, i literally fall asleep at my desk, its affecting my social life too, ive not slept more than lightly for the last year and grind through impossible code puzzles in my half sleep wich keeps me awake, when im already exhausted. plus the work is rushed and buggy when it does get done so drags on into the next project. I also procrastinate quite badly, pacing the livingroom, looking out the window when Im alone for three days straight in the flat and start to get cabin fever which means i do even less work and the negative feedback loop continues. I get told im the only one with the problem when i say that i cant work from home any more, and examples of other freelancers get brought up. an office wouldnt bring any extra cash in to the company but im convinced having that moving more than 2 meters away from my bed to go to "work" would get me working, at the moment i feel guilty like i should be working 24-7. It is important that we do all this work to raise enough cash to get our business to the next level but every month still feels like a struggle to pay the rent (there is about £20K coming in by Jan) and i have to borrow money from friends often to buy food or get a taxi to a meeting, so it is vital the money keeps coming in. (im also 20 mins late for nearly all meetings but thats a different issue) have you experienced anything similar? how can i deal with the issues ive raised? is it realistic to develop 10 sites at once? how can i improve my relationship with my business partner? do you struggle to work at home? how do you deal with that? i think if i dont get my life on track by feb i will seriously consider giving it all up, but that seems like such a waste. any ideas!!? i need help! Thanks.

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  • Windows 8 for productivity?

    - by Charles Young
    At long last I’ve started using Windows 8.  I boot from a VHD on which I have installed Office, Visio, Visual Studio, SQL Server, etc.  For a week, now, I’ve been happily writing code and documents and using Visio and PowerPoint.  I am, very much, a ‘productivity’ user rather than a content consumer.   I spend my days flitting between countless windows and browser tabs displayed across dual monitors.  I need to access a lot of different functionality and information in as fluid a fashion as possible. With that in mind, and like so many others, I was worried about Windows 8.  The Metro interface is primarily about content consumption on touch-enabled screens, and not really geared for people like me sitting in front of an 8-core non-touch laptop and an additional Samsung monitor.  I still use a mouse, not my finger.  And I create more than I consume. Clearly, Windows 8 won’t be viable for people like me unless Metro keeps out of my hair when using productivity and development tools.  With this in mind, I had long expected Microsoft to provide some mechanism for switching Metro off.  There was a registry hack in last year’s Developer Preview, but this capability has been removed.   That’s brave.  So, how have things worked out so far? Well, I am really quite surprised.  When I played with the Developer Preview last year, it was clear that Metro was unfinished and didn’t play well enough with the desktop.  Obviously I expected things to improve, but the context switching from desktop to full-screen seemed a heavy burden to place on users.  That sense of abrupt change hasn’t entirely gone away (how could it), but after a few days, I can’t say that I find it burdensome or irritating.   I’ve got used very quickly to ‘gesturing’ with my mouse at the bottom or top right corners of the screen to move between applications, using the Windows key to toggle the Start screen and generally finding my way around.   I am surprised at how effective the Start screen is, given the rather basic grouping features it provides.  Of course, I had to take control of it and sort things the way I want.  If anything, though, the Start screen provides a better navigation and application launcher tool than the old Start menu. What I didn’t expect was the way that Metro enhances the productivity story.  As I write this, I’ve got my desktop open with a maximised Word window.  However, the desktop extends only across about 85% of the width of my screen.  On the left hand side, I have a column that displays the new Metro email client.  This is currently showing me a list of emails for my main work account.  I can flip easily between different accounts and read my email within that same column.  As I work on documents, I want to be able to monitor my inbox with a quick glance. The desktop, of course, has its own snap feature.  I could run the desktop full screen and bring up Outlook and Word side by side.  However, this doesn’t begin to approach the convenience of snapping the Metro email client.  Consider that when I snap a window on the desktop, it initially takes up 50% of the screen.  Outlook doesn’t really know anything about snap, and doesn’t adjust to make effective use of the limited screen estate.  Even at 50% screen width, it is difficult to use, so forget about trying to use it in a Metro fashion. In any case, I am left with the prospect of having to manually adjust everything to view my email effectively alongside Word.  Worse, there is nothing stopping another window from overlapping and obscuring my email.  It becomes a struggle to keep sight of email as it arrives.  Of course, there is always ‘toast’ to notify me when things arrive, but if Outlook is obscured, this just feels intrusive. The beauty of the Metro snap feature is that my email reader now exists outside of my desktop.   The Metro app has been crafted to work well in the fixed width column as well as in full-screen.  It cannot be obscured by overlapping windows.  I still get notifications if I wish.  More importantly, it is clear that careful attention has been given to how things work when moving between applications when ‘snapped’.  If I decide, say to flick over to the Metro newsreader to catch up with current affairs, my desktop, rather than my email client, obligingly makes way for the reader.  With a simple gesture and click, or alternatively by pressing Windows-Tab, my desktop reappears. Another pleasant surprise is the way Windows 8 handles dual monitors.  It’s not just the fact that both screens now display the desktop task bar.  It’s that I can so easily move between Metro and the desktop on either screen.  I can only have Metro on one screen at a time which makes entire sense given the ‘full-screen’ nature of Metro apps.  Using dual monitors feels smoother and easier than previous versions of Windows. Overall then, I’m enjoying the Windows 8 improvements.  Strangely, for all the hype (“Windows reimagined”, etc.), my perception as a ‘productivity’ user is more one of evolution than revolution.  It all feels very familiar, but just better.

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  • Adaptive Connections For ADFBC

    - by Duncan Mills
    Some time ago I wrote an article on Adaptive Bindings showing how the pageDef for a an ADF UI does not have to be wedded to a fixed data control or collection / View Object. This article has proved pretty popular, so as a follow up I wanted to cover another "Adaptive" feature of your ADF applications, the ability to make multiple different connections from an Application Module, at runtime. Now, I'm sure you'll be aware that if you define your application to use a data-source rather than a hard-coded JDBC connection string, then you have the ability to change the target of that data-source after deployment to point to a different database. So that's great, but the reality of that is that this single connection is effectively fixed within the application right?  Well no, this it turns out is a common misconception. To be clear, yes a single instance of an ADF Application Module is associated with a single connection but there is nothing to stop you from creating multiple instances of the same Application Module within the application, all pointing at different connections.  If fact this has been possible for a long time using a custom extension point with code that which extends oracle.jbo.http.HttpSessionCookieFactory. This approach, however, involves writing code and no-one likes to write any more code than they need to, so, is there an easier way? Yes indeed.  It is in fact  a little publicized feature that's available in all versions of 11g, the ELEnvInfoProvider. What Does it Do?  The ELEnvInfoProvider  is  a pre-existing class (the full path is  oracle.jbo.client.ELEnvInfoProvider) which you can plug into your ApplicationModule configuration using the jbo.envinfoprovider property. Visuallty you can set this in the editor, or you can also set it directly in the bc4j.xcfg (see below for an example) . Once you have plugged in this envinfoprovider, here's the fun bit, rather than defining the hard-coded name of a datasource instead you can plug in a EL expression for the connection to use.  So what's the benefit of that? Well it allows you to defer the selection of a connection until the point in time that you instantiate the AM. To define the expression itself you'll need to do a couple of things: First of all you'll need a managed bean of some sort – e.g. a sessionScoped bean defined in your ViewController project. This will need a getter method that returns the name of the connection. Now this connection itself needs to be defined in your Application Server, and can be managed through Enterprise Manager, WLST or through MBeans. (You may need to read the documentation [http://docs.oracle.com/cd/E28280_01/web.1111/b31974/deployment_topics.htm#CHDJGBDD] here on how to configure connections at runtime if you're not familiar with this)   The EL expression (e.g. ${connectionManager.connection} is then defined in the configuration by editing the bc4j.xcfg file (there is a hyperlink directly to this file on the configuration editing screen in the Application Module editor). You simply replace the hardcoded JDBCName value with the expression.  So your cfg file would end up looking something like this (notice the reference to the ELEnvInfoProvider that I talked about earlier) <BC4JConfig version="11.1" xmlns="http://xmlns.oracle.com/bc4j/configuration">   <AppModuleConfigBag ApplicationName="oracle.demo.model.TargetAppModule">   <AppModuleConfig DeployPlatform="LOCAL"  JDBCName="${connectionManager.connection}" jbo.project="oracle.demo.model.Model" name="TargetAppModuleLocal" ApplicationName="oracle.demo.model.TargetAppModule"> <AM-Pooling jbo.doconnectionpooling="true"/> <Database jbo.locking.mode="optimistic">       <Security AppModuleJndiName="oracle.demo.model.TargetAppModule"/>    <Custom jbo.envinfoprovider="oracle.jbo.client.ELEnvInfoProvider"/> </AppModuleConfig> </AppModuleConfigBag> </BC4JConfig> Still Don't Quite Get It? So far you might be thinking, well that's fine but what difference does it make if the connection is resolved "just in time" rather than up front and changed as required through Enterprise Manager? Well a trivial example would be where you have a single application deployed to your application server, but for different users you want to connect to different databases. Because, the evaluation of the connection is deferred until you first reference the AM you have a decision point that can take the user identity into account. However, think about it for a second.  Under what circumstances does a new AM get instantiated? Well at the first reference of the AM within the application yes, but also whenever a Task Flow is entered -  if the data control scope for the Task Flow is ISOLATED.  So the reality is, that on a single screen you can embed multiple Task Flows, all of which are pointing at different database connections concurrently. Hopefully you'll find this feature useful, let me know... 

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  • "Mega Menus" for SEO [duplicate]

    - by Thought Space Designs
    This question already has an answer here: How do I handle having to many links on a webpage because of my menu 4 answers I'm using the term "Mega Menus" loosely here. I'm redesigning my WordPress site (it's going to be responsive), and as part of the redesign, I was debating incorporating some sort of descriptive menu setup. For example, normal navigation drop down menus come in the form of unordered lists of links like so: <nav> <ul> <li> <a href="#">Link1</a> </li> <li> <a href="#">Link2</a> </li> <li> <a href="#">Link3</a> <ul> <li> <a href="#">Sub Link1</a> </li> <li> <a href="#">Sub Link2</a> </li> <li> <a href="#">Sub Link3</a> </li> </ul> </li> <li> <a href="#">Link4</a> </li> </ul> </nav> What I'm looking to do is build my drop down menus with more information than your standard menu. For example, I have a top level link named "Team", and under that link, I want to make a large drop down that contains head shots, headers (in the form of styled p tags) and brief (<100 words) descriptions of each team member (only 2 currently). I want to accompany this with a "Read More" link that takes you to their actual team page. This is just one example, of course, and the other top level links would also have descriptive drop downs in the same fashion. On mobile, I was planning on hiding the "mega menu", and delivering a standard unordered list of links. Here's what I was thinking for overall structure and syntax: <nav> <ul> <li> <a href="#">Home</a> </li> <li> <a href="#">About</a> </li> <li> <a href="#">Team</a> <ul> <!-- DESKTOP --> <li class="mega-menu row"> <a class="col-sm-6" href="#"> <div class="row"> <div class="col-sm-4"> <img src="#" alt="Team Member 1" /> </div> <div class="col-sm-8"> <p class="header">Team Member 1</p> <p>Short description goes here.</p> </div> </div> </a> <a class="col-sm-6" href="#"> <!-- OTHER TEAM MEMBER INFO --> </a> </li> <!-- END DESKTOP --> <!-- MOBILE --> <li> <a href="#">Team Member 1</a> </li> <li> <a href="#">Team Member 2</a> </li> <!-- END MOBILE --> </ul> </li> <li> <a href="#">Contact</a> </li> </ul> </nav> Can anybody think of any potential SEO ramifications of doing this? I'm not going to be loading these menus full of links, so it shouldn't hurt page rank, but what are the effects of having a good bit of text and maybe even forms within nav elements? Is there such a thing as overloading nav with HTML? EDIT: Here's an example of what the menu would look like rendered on desktop. I'm currently hovering the "Team" menu, but you can't see because my mouse went away when I took the screenshot. EDIT 2: This question is not a duplicate. I'm not going to have "too many" links in my menus. I'm wondering how having images and text inside of header navigation will affect my menus. Also, I don't just want "yes, this is bad" answers. Please cite your sources and be specific with reasoning.

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  • ???? Oracle11g ????????? No.2 - v$database.CURRENT_SCN

    - by Todd Bao
    «????Oracle 11g ???????»???????????,?11.2.0.3.0?????: select current_scn from v$database union all select current_scn from v$database; ??????????SCN,??????11.2.0.1.0???????????SCN?????? ??,????11.2.0.1.0????,11.2.0.3.0????X$KCCDI(V$DATABASE?????,??CURRENT_SCN??)??,?????????SCN? ----------------------------------------------------| Id  | Operation            | Name               |----------------------------------------------------|   0 | SELECT STATEMENT     |                    ||   1 |  MERGE JOIN CARTESIAN|                    ||*  2 |   FIXED TABLE FULL   | X$KCCDI            ||   3 |   BUFFER SORT        |                    ||   4 |    VIEW              | VW_JF_SET$6E0AEE5B ||   5 |     UNION-ALL        |                    ||   6 |      FIXED TABLE FULL| X$KCCDI2           ||   7 |      FIXED TABLE FULL| X$KCCDI2           |---------------------------------------------------- ??????11.2.0.3.0???????SQL??v$database????current_scn????????:???????X$KCCDI???dicur_scn(current_scn)??????? a. ???:????union all,???????,??????????X$KCCDI2(V$DATABASE??????)?VIEW????,??X$KCCDI?X$KCCDI2????,???X$KCCDI??,??: SYS@fmw//Scripts> run  1  select current_scn from v$database  2  union all select current_scn from v$database  3  union all select current_scn from v$database  4* union all select current_scn from v$databaseCURRENT_SCN-----------    5074384    5074385    5074385    50743854 rows selected. ??,X$KCCDI?????????,??????????SCN??????SCN????????“?”SCN? b. ???:???????,??: SYS@fmw//Scripts> run  1  select current_scn,status from v$database,v$instance  2  union all  3* select current_scn,status from v$database,v$instanceCURRENT_SCN + STATUS----------- + ------------------------    5075463 + OPEN    5075464 + OPEN2 rows selected. c. ???:?????????: SYS@fmw//Scripts> run  1* select a.current_scn,b.current_scn from v$database a,v$database bCURRENT_SCN + CURRENT_SCN----------- + -----------    5078328 +     50783291 row selected. ????UNION ALL?????? d. ??,???X$KCCDI??????????????????“??”??=D,????????X$?????????$???,???????,????V$DATABASE?????????????????: SYS@fmw//Scripts> run  1  select dicur_scn from x$kccdi  2* union all select dicur_scn from x$kccdiDICUR_SCN--------------------------------508218350821842 rows selected. SYS@fmw//Scripts> run  1* select a.dicur_scn,b.dicur_scn from x$kccdi a,x$kccdi bDICUR_SCN                        + DICUR_SCN-------------------------------- + --------------------------------5082913                          + 50829141 row selected. ??? Todd Bao ??,???????????,?????????SCN,????V$DATABASE.CURRENT_SCN?,???????“next scn”? ×??,???demo????11.2.0.3.???

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  • How can I resolve Hibernate 3's ConstraintViolationException when updating a Persistent Entity's Col

    - by Tim Visher
    I'm trying to discover why two nearly identical class sets are behaving different from Hibernate 3's perspective. I'm fairly new to Hibernate in general and I'm hoping I'm missing something fairly obvious about the mappings or timing issues or something along those lines but I spent the whole day yesterday staring at the two sets and any differences that would lead to one being able to be persisted and the other not completely escaped me. I appologize in advance for the length of this question but it all hinges around some pretty specific implementation details. I have the following class mapped with Annotations and managed by Hibernate 3.? (if the specific specific version turns out to be pertinent, I'll figure out what it is). Java version is 1.6. ... @Embeddable public class JobStateChange implements Comparable<JobStateChange> { @Temporal(TemporalType.TIMESTAMP) @Column(nullable = false) private Date date; @Enumerated(EnumType.STRING) @Column(nullable = false, length = JobState.FIELD_LENGTH) private JobState state; @ManyToOne(fetch = FetchType.LAZY) @JoinColumn(name = "acting_user_id", nullable = false) private User actingUser; public JobStateChange() { } @Override public int compareTo(final JobStateChange o) { return this.date.compareTo(o.date); } @Override public boolean equals(final Object obj) { if (this == obj) { return true; } else if (!(obj instanceof JobStateChange)) { return false; } JobStateChange candidate = (JobStateChange) obj; return this.state == candidate.state && this.actingUser.equals(candidate.getUser()) && this.date.equals(candidate.getDate()); } @Override public int hashCode() { return this.state.hashCode() + this.actingUser.hashCode() + this.date.hashCode(); } } It is mapped as a Hibernate CollectionOfElements in the class Job as follows: ... @Entity @Table( name = "job", uniqueConstraints = { @UniqueConstraint( columnNames = { "agency", //Job Name "payment_type", //Job Name "payment_file", //Job Name "date_of_payment", "payment_control_number", "truck_number" }) }) public class Job implements Serializable { private static final long serialVersionUID = -1131729422634638834L; ... @org.hibernate.annotations.CollectionOfElements @JoinTable(name = "job_state", joinColumns = @JoinColumn(name = "job_id")) @Sort(type = SortType.NATURAL) private final SortedSet<JobStateChange> stateChanges = new TreeSet<JobStateChange>(); ... public void advanceState( final User actor, final Date date) { JobState nextState; LOGGER.debug("Current state of {} is {}.", this, this.getCurrentState()); if (null == this.currentState) { nextState = JobState.BEGINNING; } else { if (!this.isAdvanceable()) { throw new IllegalAdvancementException(this.currentState.illegalAdvancementStateMessage); } if (this.currentState.isDivergent()) { nextState = this.currentState.getNextState(this); } else { nextState = this.currentState.getNextState(); } } JobStateChange stateChange = new JobStateChange(nextState, actor, date); this.setCurrentState(stateChange.getState()); this.stateChanges.add(stateChange); LOGGER.debug("Advanced {} to {}", this, this.getCurrentState()); } private void setCurrentState(final JobState jobState) { this.currentState = jobState; } boolean isAdvanceable() { return this.getCurrentState().isAdvanceable(this); } ... @Override public boolean equals(final Object obj) { if (obj == this) { return true; } else if (!(obj instanceof Job)) { return false; } Job otherJob = (Job) obj; return this.getName().equals(otherJob.getName()) && this.getDateOfPayment().equals(otherJob.getDateOfPayment()) && this.getPaymentControlNumber().equals(otherJob.getPaymentControlNumber()) && this.getTruckNumber().equals(otherJob.getTruckNumber()); } @Override public int hashCode() { return this.getName().hashCode() + this.getDateOfPayment().hashCode() + this.getPaymentControlNumber().hashCode() + this.getTruckNumber().hashCode(); } ... } The purpose of JobStateChange is to record when the Job moves through a series of State Changes that are outline in JobState as enums which know about advancement and decrement rules. The interface used to advance Jobs through a series of states is to call Job.advanceState() with a Date and a User. If the Job is advanceable according to rules coded in the enum, then a new StateChange is added to the SortedSet and everyone's happy. If not, an IllegalAdvancementException is thrown. The DDL this generates is as follows: ... drop table job; drop table job_state; ... create table job ( id bigint generated by default as identity, current_state varchar(25), date_of_payment date not null, beginningCheckNumber varchar(8) not null, item_count integer, agency varchar(10) not null, payment_file varchar(25) not null, payment_type varchar(25) not null, endingCheckNumber varchar(8) not null, payment_control_number varchar(4) not null, truck_number varchar(255) not null, wrapping_system_type varchar(15) not null, printer_id bigint, primary key (id), unique (agency, payment_type, payment_file, date_of_payment, payment_control_number, truck_number) ); create table job_state ( job_id bigint not null, acting_user_id bigint not null, date timestamp not null, state varchar(25) not null, primary key (job_id, acting_user_id, date, state) ); ... alter table job add constraint FK19BBD12FB9D70 foreign key (printer_id) references printer; alter table job_state add constraint FK57C2418FED1F0D21 foreign key (acting_user_id) references app_user; alter table job_state add constraint FK57C2418FABE090B3 foreign key (job_id) references job; ... The database is seeded with the following data prior to running tests ... insert into job (id, agency, payment_type, payment_file, payment_control_number, date_of_payment, beginningCheckNumber, endingCheckNumber, item_count, current_state, printer_id, wrapping_system_type, truck_number) values (-3, 'RRB', 'Monthly', 'Monthly','4501','1998-12-01 08:31:16' , '00000001','00040000', 40000, 'UNASSIGNED', null, 'KERN', '02'); insert into job_state (job_id, acting_user_id, date, state) values (-3, -1, '1998-11-30 08:31:17', 'UNASSIGNED'); ... After the database schema is automatically generated and rebuilt by the Hibernate tool. The following test runs fine up until the call to Session.flush() ... @ContextConfiguration(locations = { "/applicationContext-data.xml", "/applicationContext-service.xml" }) public class JobDaoIntegrationTest extends AbstractTransactionalJUnit4SpringContextTests { @Autowired private JobDao jobDao; @Autowired private SessionFactory sessionFactory; @Autowired private UserService userService; @Autowired private PrinterService printerService; ... @Test public void saveJob_JobAdvancedToAssigned_AllExpectedStateChanges() { //Get an unassigned Job Job job = this.jobDao.getJob(-3L); assertEquals(JobState.UNASSIGNED, job.getCurrentState()); Date advancedToUnassigned = new GregorianCalendar(1998, 10, 30, 8, 31, 17).getTime(); assertEquals(advancedToUnassigned, job.getStateChange(JobState.UNASSIGNED).getDate()); //Satisfy advancement constraints and advance job.setPrinter(this.printerService.getPrinter(-1L)); Date advancedToAssigned = new Date(); job.advanceState( this.userService.getUserByUsername("admin"), advancedToAssigned); assertEquals(JobState.ASSIGNED, job.getCurrentState()); assertEquals(advancedToUnassigned, job.getStateChange(JobState.UNASSIGNED).getDate()); assertEquals(advancedToAssigned, job.getStateChange(JobState.ASSIGNED).getDate()); //Persist to DB this.sessionFactory.getCurrentSession().flush(); ... } ... } The error thrown is SQLCODE=-803, SQLSTATE=23505: could not insert collection rows: [jaci.model.job.Job.stateChanges#-3] org.hibernate.exception.ConstraintViolationException: could not insert collection rows: [jaci.model.job.Job.stateChanges#-3] at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:94) at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:66) at org.hibernate.persister.collection.AbstractCollectionPersister.insertRows(AbstractCollectionPersister.java:1416) at org.hibernate.action.CollectionUpdateAction.execute(CollectionUpdateAction.java:86) at org.hibernate.engine.ActionQueue.execute(ActionQueue.java:279) at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:263) at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:170) at org.hibernate.event.def.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:321) at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:50) at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1027) at jaci.dao.JobDaoIntegrationTest.saveJob_JobAdvancedToAssigned_AllExpectedStateChanges(JobDaoIntegrationTest.java:98) at org.springframework.test.context.junit4.SpringTestMethod.invoke(SpringTestMethod.java:160) at org.springframework.test.context.junit4.SpringMethodRoadie.runTestMethod(SpringMethodRoadie.java:233) at org.springframework.test.context.junit4.SpringMethodRoadie$RunBeforesThenTestThenAfters.run(SpringMethodRoadie.java:333) at org.springframework.test.context.junit4.SpringMethodRoadie.runWithRepetitions(SpringMethodRoadie.java:217) at org.springframework.test.context.junit4.SpringMethodRoadie.runTest(SpringMethodRoadie.java:197) at org.springframework.test.context.junit4.SpringMethodRoadie.run(SpringMethodRoadie.java:143) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.invokeTestMethod(SpringJUnit4ClassRunner.java:160) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:97) Caused by: com.ibm.db2.jcc.b.lm: DB2 SQL Error: SQLCODE=-803, SQLSTATE=23505, SQLERRMC=1;ACI_APP.JOB_STATE, DRIVER=3.50.152 at com.ibm.db2.jcc.b.wc.a(wc.java:575) at com.ibm.db2.jcc.b.wc.a(wc.java:57) at com.ibm.db2.jcc.b.wc.a(wc.java:126) at com.ibm.db2.jcc.b.tk.b(tk.java:1593) at com.ibm.db2.jcc.b.tk.c(tk.java:1576) at com.ibm.db2.jcc.t4.db.k(db.java:353) at com.ibm.db2.jcc.t4.db.a(db.java:59) at com.ibm.db2.jcc.t4.t.a(t.java:50) at com.ibm.db2.jcc.t4.tb.b(tb.java:200) at com.ibm.db2.jcc.b.uk.Gb(uk.java:2355) at com.ibm.db2.jcc.b.uk.e(uk.java:3129) at com.ibm.db2.jcc.b.uk.zb(uk.java:568) at com.ibm.db2.jcc.b.uk.executeUpdate(uk.java:551) at org.hibernate.jdbc.NonBatchingBatcher.addToBatch(NonBatchingBatcher.java:46) at org.hibernate.persister.collection.AbstractCollectionPersister.insertRows(AbstractCollectionPersister.java:1389) Therein lies my problem… A nearly identical Class set (in fact, so identical that I've been chomping at the bit to make it a single class that serves both business entities) runs absolutely fine. It is identical except for name. Instead of Job it's Web. Instead of JobStateChange it's WebStateChange. Instead of JobState it's WebState. Both Job and Web's SortedSet of StateChanges are mapped as a Hibernate CollectionOfElements. Both are @Embeddable. Both are SortType.Natural. Both are backed by an Enumeration with some advancement rules in it. And yet when a nearly identical test is run for Web, no issue is discovered and the data flushes fine. For the sake of brevity I won't include all of the Web classes here, but I will include the test and if anyone wants to see the actual sources, I'll include them (just leave a comment). The data seed: insert into web (id, stock_type, pallet, pallet_id, date_received, first_icn, last_icn, shipment_id, current_state) values (-1, 'PF', '0011', 'A', '2008-12-31 08:30:02', '000000001', '000080000', -1, 'UNSTAGED'); insert into web_state (web_id, date, state, acting_user_id) values (-1, '2008-12-31 08:30:03', 'UNSTAGED', -1); The test: ... @ContextConfiguration(locations = { "/applicationContext-data.xml", "/applicationContext-service.xml" }) public class WebDaoIntegrationTest extends AbstractTransactionalJUnit4SpringContextTests { @Autowired private WebDao webDao; @Autowired private UserService userService; @Autowired private SessionFactory sessionFactory; ... @Test public void saveWeb_WebAdvancedToNewState_AllExpectedStateChanges() { Web web = this.webDao.getWeb(-1L); Date advancedToUnstaged = new GregorianCalendar(2008, 11, 31, 8, 30, 3).getTime(); assertEquals(WebState.UNSTAGED, web.getCurrentState()); assertEquals(advancedToUnstaged, web.getState(WebState.UNSTAGED).getDate()); Date advancedToStaged = new Date(); web.advanceState( this.userService.getUserByUsername("admin"), advancedToStaged); this.sessionFactory.getCurrentSession().flush(); web = this.webDao.getWeb(web.getId()); assertEquals( "Web should have moved to STAGED State.", WebState.STAGED, web.getCurrentState()); assertEquals(advancedToUnstaged, web.getState(WebState.UNSTAGED).getDate()); assertEquals(advancedToStaged, web.getState(WebState.STAGED).getDate()); assertNotNull(web.getState(WebState.UNSTAGED)); assertNotNull(web.getState(WebState.STAGED)); } ... } As you can see, I assert that the Web was reconstituted the way I expect, I advance it, flush it to the DB, and then re-get it and verify that the states are as I expect. Everything works perfectly. Not so with Job. A possibly pertinent detail: the reconstitution code works fine if I cease to map JobStateChange.data as a TIMESTAMP and instead as a DATE, and ensure that all of the StateChanges always occur on different Dates. The problem is that this particular business entity can go through many state changes in a single day and so it needs to be sorted by time stamp rather than by date. If I don't do this then I can't sort the StateChanges correctly. That being said, WebStateChange.date is also mapped as a TIMESTAMP and so I again remain absolutely befuddled as to where this error is arising from. I tried to do a fairly thorough job of giving all of the technical details of the implementation but as this particular question is very implementation specific, if I missed anything just let me know in the comments and I'll include it. Thanks so much for your help! UPDATE: Since it turns out to be important to the solution of my problem, I have to include the pertinent bits of the WebStateChange class as well. ... @Embeddable public class WebStateChange implements Comparable<WebStateChange> { @Temporal(TemporalType.TIMESTAMP) @Column(nullable = false) private Date date; @Enumerated(EnumType.STRING) @Column(nullable = false, length = WebState.FIELD_LENGTH) private WebState state; @ManyToOne(fetch = FetchType.LAZY) @JoinColumn(name = "acting_user_id", nullable = false) private User actingUser; ... WebStateChange( final WebState state, final User actingUser, final Date date) { ExceptionUtils.illegalNullArgs(state, actingUser, date); this.state = state; this.actingUser = actingUser; this.date = new Date(date.getTime()); } @Override public int compareTo(final WebStateChange otherStateChange) { return this.date.compareTo(otherStateChange.date); } @Override public boolean equals(final Object candidate) { if (this == candidate) { return true; } else if (!(candidate instanceof WebStateChange)) { return false; } WebStateChange candidateWebState = (WebStateChange) candidate; return this.getState() == candidateWebState.getState() && this.getUser().equals(candidateWebState.getUser()) && this.getDate().equals(candidateWebState.getDate()); } @Override public int hashCode() { return this.getState().hashCode() + this.getUser().hashCode() + this.getDate().hashCode(); } ... }

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  • Bulk inserting best way to about it? + Helping me understand fully what I found so far

    - by chobo2
    Hi So I saw this post here and read it and it seems like bulk copy might be the way to go. http://stackoverflow.com/questions/682015/whats-the-best-way-to-bulk-database-inserts-from-c I still have some questions and want to know how things actually work. So I found 2 tutorials. http://www.codeproject.com/KB/cs/MultipleInsertsIn1dbTrip.aspx#_Toc196622241 http://www.codeproject.com/KB/linq/BulkOperations_LinqToSQL.aspx First way uses 2 ado.net 2.0 features. BulkInsert and BulkCopy. the second one uses linq to sql and OpenXML. This sort of appeals to me as I am using linq to sql already and prefer it over ado.net. However as one person pointed out in the posts what he just going around the issue at the cost of performance( nothing wrong with that in my opinion) First I will talk about the 2 ways in the first tutorial I am using VS2010 Express, .net 4.0, MVC 2.0, SQl Server 2005 Is ado.net 2.0 the most current version? Based on the technology I am using, is there some updates to what I am going to show that would improve it somehow? Is there any thing that these tutorial left out that I should know about? BulkInsert I am using this table for all the examples. CREATE TABLE [dbo].[TBL_TEST_TEST] ( ID INT IDENTITY(1,1) PRIMARY KEY, [NAME] [varchar](50) ) SP Code USE [Test] GO /****** Object: StoredProcedure [dbo].[sp_BatchInsert] Script Date: 05/19/2010 15:12:47 ******/ SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO ALTER PROCEDURE [dbo].[sp_BatchInsert] (@Name VARCHAR(50) ) AS BEGIN INSERT INTO TBL_TEST_TEST VALUES (@Name); END C# Code /// <summary> /// Another ado.net 2.0 way that uses a stored procedure to do a bulk insert. /// Seems slower then "BatchBulkCopy" way and it crashes when you try to insert 500,000 records in one go. /// http://www.codeproject.com/KB/cs/MultipleInsertsIn1dbTrip.aspx#_Toc196622241 /// </summary> private static void BatchInsert() { // Get the DataTable with Rows State as RowState.Added DataTable dtInsertRows = GetDataTable(); SqlConnection connection = new SqlConnection(connectionString); SqlCommand command = new SqlCommand("sp_BatchInsert", connection); command.CommandType = CommandType.StoredProcedure; command.UpdatedRowSource = UpdateRowSource.None; // Set the Parameter with appropriate Source Column Name command.Parameters.Add("@Name", SqlDbType.VarChar, 50, dtInsertRows.Columns[0].ColumnName); SqlDataAdapter adpt = new SqlDataAdapter(); adpt.InsertCommand = command; // Specify the number of records to be Inserted/Updated in one go. Default is 1. adpt.UpdateBatchSize = 1000; connection.Open(); int recordsInserted = adpt.Update(dtInsertRows); connection.Close(); } So first thing is the batch size. Why would you set a batch size to anything but the number of records you are sending? Like I am sending 500,000 records so I did a Batch size of 500,000. Next why does it crash when I do this? If I set it to 1000 for batch size it works just fine. System.Data.SqlClient.SqlException was unhandled Message="A transport-level error has occurred when sending the request to the server. (provider: Shared Memory Provider, error: 0 - No process is on the other end of the pipe.)" Source=".Net SqlClient Data Provider" ErrorCode=-2146232060 Class=20 LineNumber=0 Number=233 Server="" State=0 StackTrace: at System.Data.Common.DbDataAdapter.UpdatedRowStatusErrors(RowUpdatedEventArgs rowUpdatedEvent, BatchCommandInfo[] batchCommands, Int32 commandCount) at System.Data.Common.DbDataAdapter.UpdatedRowStatus(RowUpdatedEventArgs rowUpdatedEvent, BatchCommandInfo[] batchCommands, Int32 commandCount) at System.Data.Common.DbDataAdapter.Update(DataRow[] dataRows, DataTableMapping tableMapping) at System.Data.Common.DbDataAdapter.UpdateFromDataTable(DataTable dataTable, DataTableMapping tableMapping) at System.Data.Common.DbDataAdapter.Update(DataTable dataTable) at TestIQueryable.Program.BatchInsert() in C:\Users\a\Downloads\TestIQueryable\TestIQueryable\TestIQueryable\Program.cs:line 124 at TestIQueryable.Program.Main(String[] args) in C:\Users\a\Downloads\TestIQueryable\TestIQueryable\TestIQueryable\Program.cs:line 16 InnerException: Time it took to insert 500,000 records with insert batch size of 1000 took "2 mins and 54 seconds" Of course this is no official time I sat there with a stop watch( I am sure there are better ways but was too lazy to look what they where) So I find that kinda slow compared to all my other ones(expect the linq to sql insert one) and I am not really sure why. Next I looked at bulkcopy /// <summary> /// An ado.net 2.0 way to mass insert records. This seems to be the fastest. /// http://www.codeproject.com/KB/cs/MultipleInsertsIn1dbTrip.aspx#_Toc196622241 /// </summary> private static void BatchBulkCopy() { // Get the DataTable DataTable dtInsertRows = GetDataTable(); using (SqlBulkCopy sbc = new SqlBulkCopy(connectionString, SqlBulkCopyOptions.KeepIdentity)) { sbc.DestinationTableName = "TBL_TEST_TEST"; // Number of records to be processed in one go sbc.BatchSize = 500000; // Map the Source Column from DataTabel to the Destination Columns in SQL Server 2005 Person Table // sbc.ColumnMappings.Add("ID", "ID"); sbc.ColumnMappings.Add("NAME", "NAME"); // Number of records after which client has to be notified about its status sbc.NotifyAfter = dtInsertRows.Rows.Count; // Event that gets fired when NotifyAfter number of records are processed. sbc.SqlRowsCopied += new SqlRowsCopiedEventHandler(sbc_SqlRowsCopied); // Finally write to server sbc.WriteToServer(dtInsertRows); sbc.Close(); } } This one seemed to go really fast and did not even need a SP( can you use SP with bulk copy? If you can would it be better?) BatchCopy had no problem with a 500,000 batch size.So again why make it smaller then the number of records you want to send? I found that with BatchCopy and 500,000 batch size it took only 5 seconds to complete. I then tried with a batch size of 1,000 and it only took 8 seconds. So much faster then the bulkinsert one above. Now I tried the other tutorial. USE [Test] GO /****** Object: StoredProcedure [dbo].[spTEST_InsertXMLTEST_TEST] Script Date: 05/19/2010 15:39:03 ******/ SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO ALTER PROCEDURE [dbo].[spTEST_InsertXMLTEST_TEST](@UpdatedProdData nText) AS DECLARE @hDoc int exec sp_xml_preparedocument @hDoc OUTPUT,@UpdatedProdData INSERT INTO TBL_TEST_TEST(NAME) SELECT XMLProdTable.NAME FROM OPENXML(@hDoc, 'ArrayOfTBL_TEST_TEST/TBL_TEST_TEST', 2) WITH ( ID Int, NAME varchar(100) ) XMLProdTable EXEC sp_xml_removedocument @hDoc C# code. /// <summary> /// This is using linq to sql to make the table objects. /// It is then serailzed to to an xml document and sent to a stored proedure /// that then does a bulk insert(I think with OpenXML) /// http://www.codeproject.com/KB/linq/BulkOperations_LinqToSQL.aspx /// </summary> private static void LinqInsertXMLBatch() { using (TestDataContext db = new TestDataContext()) { TBL_TEST_TEST[] testRecords = new TBL_TEST_TEST[500000]; for (int count = 0; count < 500000; count++) { TBL_TEST_TEST testRecord = new TBL_TEST_TEST(); testRecord.NAME = "Name : " + count; testRecords[count] = testRecord; } StringBuilder sBuilder = new StringBuilder(); System.IO.StringWriter sWriter = new System.IO.StringWriter(sBuilder); XmlSerializer serializer = new XmlSerializer(typeof(TBL_TEST_TEST[])); serializer.Serialize(sWriter, testRecords); db.insertTestData(sBuilder.ToString()); } } So I like this because I get to use objects even though it is kinda redundant. I don't get how the SP works. Like I don't get the whole thing. I don't know if OPENXML has some batch insert under the hood but I do not even know how to take this example SP and change it to fit my tables since like I said I don't know what is going on. I also don't know what would happen if the object you have more tables in it. Like say I have a ProductName table what has a relationship to a Product table or something like that. In linq to sql you could get the product name object and make changes to the Product table in that same object. So I am not sure how to take that into account. I am not sure if I would have to do separate inserts or what. The time was pretty good for 500,000 records it took 52 seconds The last way of course was just using linq to do it all and it was pretty bad. /// <summary> /// This is using linq to sql to to insert lots of records. /// This way is slow as it uses no mass insert. /// Only tried to insert 50,000 records as I did not want to sit around till it did 500,000 records. /// http://www.codeproject.com/KB/linq/BulkOperations_LinqToSQL.aspx /// </summary> private static void LinqInsertAll() { using (TestDataContext db = new TestDataContext()) { db.CommandTimeout = 600; for (int count = 0; count < 50000; count++) { TBL_TEST_TEST testRecord = new TBL_TEST_TEST(); testRecord.NAME = "Name : " + count; db.TBL_TEST_TESTs.InsertOnSubmit(testRecord); } db.SubmitChanges(); } } I did only 50,000 records and that took over a minute to do. So I really narrowed it done to the linq to sql bulk insert way or bulk copy. I am just not sure how to do it when you have relationship for either way. I am not sure how they both stand up when doing updates instead of inserts as I have not gotten around to try it yet. I don't think I will ever need to insert/update more than 50,000 records at one type but at the same time I know I will have to do validation on records before inserting so that will slow it down and that sort of makes linq to sql nicer as your got objects especially if your first parsing data from a xml file before you insert into the database. Full C# code using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Xml.Serialization; using System.Data; using System.Data.SqlClient; namespace TestIQueryable { class Program { private static string connectionString = ""; static void Main(string[] args) { BatchInsert(); Console.WriteLine("done"); } /// <summary> /// This is using linq to sql to to insert lots of records. /// This way is slow as it uses no mass insert. /// Only tried to insert 50,000 records as I did not want to sit around till it did 500,000 records. /// http://www.codeproject.com/KB/linq/BulkOperations_LinqToSQL.aspx /// </summary> private static void LinqInsertAll() { using (TestDataContext db = new TestDataContext()) { db.CommandTimeout = 600; for (int count = 0; count < 50000; count++) { TBL_TEST_TEST testRecord = new TBL_TEST_TEST(); testRecord.NAME = "Name : " + count; db.TBL_TEST_TESTs.InsertOnSubmit(testRecord); } db.SubmitChanges(); } } /// <summary> /// This is using linq to sql to make the table objects. /// It is then serailzed to to an xml document and sent to a stored proedure /// that then does a bulk insert(I think with OpenXML) /// http://www.codeproject.com/KB/linq/BulkOperations_LinqToSQL.aspx /// </summary> private static void LinqInsertXMLBatch() { using (TestDataContext db = new TestDataContext()) { TBL_TEST_TEST[] testRecords = new TBL_TEST_TEST[500000]; for (int count = 0; count < 500000; count++) { TBL_TEST_TEST testRecord = new TBL_TEST_TEST(); testRecord.NAME = "Name : " + count; testRecords[count] = testRecord; } StringBuilder sBuilder = new StringBuilder(); System.IO.StringWriter sWriter = new System.IO.StringWriter(sBuilder); XmlSerializer serializer = new XmlSerializer(typeof(TBL_TEST_TEST[])); serializer.Serialize(sWriter, testRecords); db.insertTestData(sBuilder.ToString()); } } /// <summary> /// An ado.net 2.0 way to mass insert records. This seems to be the fastest. /// http://www.codeproject.com/KB/cs/MultipleInsertsIn1dbTrip.aspx#_Toc196622241 /// </summary> private static void BatchBulkCopy() { // Get the DataTable DataTable dtInsertRows = GetDataTable(); using (SqlBulkCopy sbc = new SqlBulkCopy(connectionString, SqlBulkCopyOptions.KeepIdentity)) { sbc.DestinationTableName = "TBL_TEST_TEST"; // Number of records to be processed in one go sbc.BatchSize = 500000; // Map the Source Column from DataTabel to the Destination Columns in SQL Server 2005 Person Table // sbc.ColumnMappings.Add("ID", "ID"); sbc.ColumnMappings.Add("NAME", "NAME"); // Number of records after which client has to be notified about its status sbc.NotifyAfter = dtInsertRows.Rows.Count; // Event that gets fired when NotifyAfter number of records are processed. sbc.SqlRowsCopied += new SqlRowsCopiedEventHandler(sbc_SqlRowsCopied); // Finally write to server sbc.WriteToServer(dtInsertRows); sbc.Close(); } } /// <summary> /// Another ado.net 2.0 way that uses a stored procedure to do a bulk insert. /// Seems slower then "BatchBulkCopy" way and it crashes when you try to insert 500,000 records in one go. /// http://www.codeproject.com/KB/cs/MultipleInsertsIn1dbTrip.aspx#_Toc196622241 /// </summary> private static void BatchInsert() { // Get the DataTable with Rows State as RowState.Added DataTable dtInsertRows = GetDataTable(); SqlConnection connection = new SqlConnection(connectionString); SqlCommand command = new SqlCommand("sp_BatchInsert", connection); command.CommandType = CommandType.StoredProcedure; command.UpdatedRowSource = UpdateRowSource.None; // Set the Parameter with appropriate Source Column Name command.Parameters.Add("@Name", SqlDbType.VarChar, 50, dtInsertRows.Columns[0].ColumnName); SqlDataAdapter adpt = new SqlDataAdapter(); adpt.InsertCommand = command; // Specify the number of records to be Inserted/Updated in one go. Default is 1. adpt.UpdateBatchSize = 500000; connection.Open(); int recordsInserted = adpt.Update(dtInsertRows); connection.Close(); } private static DataTable GetDataTable() { // You First need a DataTable and have all the insert values in it DataTable dtInsertRows = new DataTable(); dtInsertRows.Columns.Add("NAME"); for (int i = 0; i < 500000; i++) { DataRow drInsertRow = dtInsertRows.NewRow(); string name = "Name : " + i; drInsertRow["NAME"] = name; dtInsertRows.Rows.Add(drInsertRow); } return dtInsertRows; } static void sbc_SqlRowsCopied(object sender, SqlRowsCopiedEventArgs e) { Console.WriteLine("Number of records affected : " + e.RowsCopied.ToString()); } } }

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