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• Database model for keeping track of likes/shares/comments on blog posts over time

  - by gage

  My goal is to keep track of the popular posts on different blog sites based on social network activity at any given time. The goal is not to simply get the most popular now, but instead find posts that are popular compared to other posts on the same blog. For example, I follow a tech blog, a sports blog, and a gossip blog. The tech blog gets waaay more readership than the other two blogs, so in raw numbers every post on the tech blog will always out number views on the other two. So lets say the average tech blog post gets 500 facebook likes and the other two get an average of 50 likes per post. Then when there is a sports blog post that has 200 fb likes and a gossip blog post with 300 while the tech blog posts today have 500 likes I want to highlight the sports and gossip blog posts (more likes than average vs tech blog with more # of likes but just average for the blog) The approach I am thinking of taking is to make an entry in a database for each blog post. Every x minutes (say every 15 minutes) I will check how many likes/shares/comments an entry has received on all the social networks (facebook, twitter, google+, linkeIn). So over time there will be a history of likes for each blog post, i.e post 1234 after 15 min: 10 fb likes, 4 tweets, 6 g+ after 30 min: 15 fb likes, 15 tweets, 10 g+ ... ... after 48 hours: 200 fb likes, 25 tweets, 15 g+ By keeping a history like this for each blog post I can know the average number of likes/shares/tweets at any give time interval. So for example the average number of fb likes for all blog posts 48hrs after posting is 50, and a particular post has 200 I can mark that as a popular post and feature/highlight it. A consideration in the design is to be able to easily query the values (likes/shares) for a specific time-frame, i.e. fb likes after 30min or tweets after 24 hrs in-order to compute averages with which to compare against (or should averages be stored in it's own table?) If this approach is flawed or could use improvement please let me know, but it is not my main question. My main question is what should a database scheme for storing this info look like? Assuming that the above approach is taken I am trying to figure out what a database schema for storing the likes over time would look like. I am brand new to databases, in doing some basic reading I see that it is advisable to make a 3NF database. I have come up with the following possible schema. Schema 1 DB Popular Posts Table: Post post_id ( primary key(pk) ) url title Table: Social Activity activity_id (pk) url (fk) type (i.e. facebook,twitter,g+) value timestamp This was my initial instinct (base on my very limited db knowledge). As far as I under stand this schema would be 3NF? I searched for designs of similar database model, and found this question on stackoverflow, http://stackoverflow.com/questions/11216080/data-structure-for-storing-height-and-weight-etc-over-time-for-multiple-users . The scenario in that question is similar (recording weight/height of users overtime). Taking the accepted answer for that question and applying it to my model results in something like: Schema 2 (same as above, but break down the social activity into 2 tables) DB Popular Posts Table: Post post_id (pk) url title Table: Social Measurement measurement_id (pk) post_id (fk) timestamp Table: Social stat stat_id (pk) measurement_id (fk) type (i.e. facebook,twitter,g+) value The advantage I see in schema 2 is that I will likely want to access all the values for a given time, i.e. when making a measurement at 30min after a post is published I will simultaneous check number of fb likes, fb shares, fb comments, tweets, g+, linkedIn. So with this schema it may be easier get get all stats for a measurement_id corresponding to a certain time, i.e. all social stats for post 1234 at time x. Another thought I had is since it doesn't make sense to compare number of fb likes with number of tweets or g+ shares, maybe it makes sense to separate each social measurement into it's own table? Schema 3 DB Popular Posts Table: Post post_id (pk) url title Table: fb_likes fb_like_id (pk) post_id (fk) timestamp value Table: fb_shares fb_shares_id (pk) post_id (fk) timestamp value Table: tweets tweets__id (pk) post_id (fk) timestamp value Table: google_plus google_plus_id (pk) post_id (fk) timestamp value As you can see I am generally lost/unsure of what approach to take. I'm sure this typical type of database problem (storing measurements overtime, i.e temperature statistic) that must have a common solution. Is there a design pattern/model for this, does it have a name? I tried searching for "database periodic data collection" or "database measurements over time" but didn't find anything specific. What would be an appropriate model to solve the needs of this problem?

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• 8 Backup Tools Explained for Windows 7 and 8

  - by Chris Hoffman

  Backups on Windows can be confusing. Whether you’re using Windows 7 or 8, you have quite a few integrated backup tools to think about. Windows 8 made quite a few changes, too. You can also use third-party backup software, whether you want to back up to an external drive or back up your files to online storage. We won’t cover third-party tools here — just the ones built into Windows. Backup and Restore on Windows 7 Windows 7 has its own Backup and Restore feature that lets you create backups manually or on a schedule. You’ll find it under Backup and Restore in the Control Panel. The original version of Windows 8 still contained this tool, and named it Windows 7 File Recovery. This allowed former Windows 7 users to restore files from those old Windows 7 backups or keep using the familiar backup tool for a little while. Windows 7 File Recovery was removed in Windows 8.1. System Restore System Restore on both Windows 7 and 8 functions as a sort of automatic system backup feature. It creates backup copies of important system and program files on a schedule or when you perform certain tasks, such as installing a hardware driver. If system files become corrupted or your computer’s software becomes unstable, you can use System Restore to restore your system and program files from a System Restore point. This isn’t a way to back up your personal files. It’s more of a troubleshooting feature that uses backups to restore your system to its previous working state. Previous Versions on Windows 7 Windows 7′s Previous Versions feature allows you to restore older versions of files — or deleted files. These files can come from backups created with Windows 7′s Backup and Restore feature, but they can also come from System Restore points. When Windows 7 creates a System Restore point, it will sometimes contain your personal files. Previous Versions allows you to extract these personal files from restore points. This only applies to Windows 7. On Windows 8, System Restore won’t create backup copies of your personal files. The Previous Versions feature was removed on Windows 8. File History Windows 8 replaced Windows 7′s backup tools with File History, although this feature isn’t enabled by default. File History is designed to be a simple, easy way to create backups of your data files on an external drive or network location. File History replaces both Windows 7′s Backup and Previous Versions features. Windows System Restore won’t create copies of personal files on Windows 8. This means you can’t actually recover older versions of files until you enable File History yourself — it isn’t enabled by default. System Image Backups Windows also allows you to create system image backups. These are backup images of your entire operating system, including your system files, installed programs, and personal files. This feature was included in both Windows 7 and Windows 8, but it was hidden in the preview versions of Windows 8.1. After many user complaints, it was restored and is still available in the final version of Windows 8.1 — click System Image Backup on the File History Control Panel. Storage Space Mirroring Windows 8′s Storage Spaces feature allows you to set up RAID-like features in software. For example, you can use Storage Space to set up two hard disks of the same size in a mirroring configuration. They’ll appear as a single drive in Windows. When you write to this virtual drive, the files will be saved to both physical drives. If one drive fails, your files will still be available on the other drive. This isn’t a good long-term backup solution, but it is a way of ensuring you won’t lose important files if a single drive fails. Microsoft Account Settings Backup Windows 8 and 8.1 allow you to back up a variety of system settings — including personalization, desktop, and input settings. If you’re signing in with a Microsoft account, OneDrive settings backup is enabled automatically. This feature can be controlled under OneDrive > Sync settings in the PC settings app. This feature only backs up a few settings. It’s really more of a way to sync settings between devices. OneDrive Cloud Storage Microsoft hasn’t been talking much about File History since Windows 8 was released. That’s because they want people to use OneDrive instead. OneDrive — formerly known as SkyDrive — was added to the Windows desktop in Windows 8.1. Save your files here and they’ll be stored online tied to your Microsoft account. You can then sign in on any other computer, smartphone, tablet, or even via the web and access your files. Microsoft wants typical PC users “backing up” their files with OneDrive so they’ll be available on any device. You don’t have to worry about all these features. Just choose a backup strategy to ensure your files are safe if your computer’s hard disk fails you. Whether it’s an integrated backup tool or a third-party backup application, be sure to back up your files.

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• Entity Framework 4.0: Creating objects of correct type when using lazy loading

  - by DigiMortal

  In my posting about Entity Framework 4.0 and POCOs I introduced lazy loading in EF applications. EF uses proxy classes for lazy loading and this means we have new types in that come and go dynamically in runtime. We don’t have these types available when we write code but we cannot forget that EF may expect us to use dynamically generated types. In this posting I will give you simple hint how to use correct types in your code. The background of lazy loading and proxy classes As a first thing I will explain you in short what is proxy class. Business classes when designed correctly have no knowledge about their birth and death – they don’t know how they are created and they don’t know how their data is persisted. This is the responsibility of object runtime. When we use lazy loading we need a little bit different classes that know how to load data for properties when code accesses the property first time. As we cannot add this functionality to our business classes (they may be stored through more than one data access technology or by more than one Data Access Layer (DAL)) we create proxy classes that extend our business classes. If we have class called Product and product has lazy loaded property called Customer then we need proxy class, let’s say ProductProxy, that has same public signature as Product so we can use it INSTEAD OF product in our code. ProductProxy overrides Customer property. If customer is not asked then customer is null. But if we ask for Customer property then overridden property of ProductProxy loads it from database. This is how lazy loading works. Problem – two types for same thing As lazy loading may introduce dynamically generated proxy types we don’t know in our application code which type is returned. We cannot be sure that we have Product not ProductProxy returned. This leads us to the following question: how can we create Product of correct type if we don’t know the correct type? In EF solution is simple. Solution – use factory methods If you are using repositories and you are not using factories (imho it is pretty pointless with mapper) you can add factory methods to your EF based repositories. Take a look at this class. public class Event {     public int ID { get; set; }     public string Title { get; set; }     public string Location { get; set; }     public virtual Party Organizer { get; set; }     public DateTime Date { get; set; } } We have virtual member called Organizer. This property is virtual because we want to use lazy loading on this class so Organizer is loaded only when we ask it. EF provides us with method called CreateObject<T>(). CreateObject<T>() is member of ObjectContext class and it creates the object based on given type. In runtime proxy type for Event is created for us automatically and when we call CreateObject<T>() for Event it returns as object of Event proxy type. The factory method for events repository is as follows. public Event CreateEvent() {     var evt = _context.CreateObject<Event>();     return evt; } And we are done. Instead of creating factory classes we created factory methods that guarantee that created objects are of correct type. Conclusion Although lazy loading introduces some new objects we cannot use at design time because they live only in runtime we can write code without worrying about exact implementation type of object. This holds true until we have clean code and we don’t make any decisions based on object type. EF4.0 provides us with very simple factory method that create and return objects of correct type. All we had to do was adding factory methods to our repositories.

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• Form, function and complexity in rule processing

  - by Charles Young

  Tim Bass posted on ‘Orwellian Event Processing’. I was involved in a heated exchange in the comments, and he has more recently published a post entitled ‘Disadvantages of Rule-Based Systems (Part 1)’. Whatever the rights and wrongs of our exchange, it clearly failed to generate any agreement or understanding of our different positions. I don't particularly want to promote further argument of that kind, but I do want to take the opportunity of offering a different perspective on rule-processing and an explanation of my comments. For me, the ‘red rag’ lay in Tim’s claim that “...rules alone are highly inefficient for most classes of (not simple) problems” and a later paragraph that appears to equate the simplicity of form (‘IF-THEN-ELSE’) with simplicity of function.   It is not the first time Tim has expressed these views and not the first time I have responded to his assertions.   Indeed, Tim has a long history of commenting on the subject of complex event processing (CEP) and, less often, rule processing in ‘robust’ terms, often asserting that very many other people’s opinions on this subject are mistaken.   In turn, I am of the opinion that, certainly in terms of rule processing, which is an area in which I have a specific interest and knowledge, he is often mistaken. There is no simple answer to the fundamental question ‘what is a rule?’ We use the word in a very fluid fashion in English. Likewise, the term ‘rule processing’, as used widely in IT, is equally difficult to define simplistically. The best way to envisage the term is as a ‘centre of gravity’ within a wider domain. That domain contains many other ‘centres of gravity’, including CEP, statistical analytics, neural networks, natural language processing and so much more. Whole communities tend to gravitate towards and build themselves around some of these centres. The term 'rule processing' is associated with many different technology types, various software products, different architectural patterns, the functional capability of many applications and services, etc. There is considerable variation amongst these different technologies, techniques and products. Very broadly, a common theme is their ability to manage certain types of processing and problem solving through declarative, or semi-declarative, statements of propositional logic bound to action-based consequences. It is generally important to be able to decouple these statements from other parts of an overall system or architecture so that they can be managed and deployed independently.  As a centre of gravity, ‘rule processing’ is no island. It exists in the context of a domain of discourse that is, itself, highly interconnected and continuous.   Rule processing does not, for example, exist in splendid isolation to natural language processing.   On the contrary, an on-going theme of rule processing is to find better ways to express rules in natural language and map these to executable forms.   Rule processing does not exist in splendid isolation to CEP.   On the contrary, an event processing agent can reasonably be considered as a rule engine (a theme in ‘Power of Events’ by David Luckham).   Rule processing does not live in splendid isolation to statistical approaches such as Bayesian analytics. On the contrary, rule processing and statistical analytics are highly synergistic.   Rule processing does not even live in splendid isolation to neural networks. For example, significant research has centred on finding ways to translate trained nets into explicit rule sets in order to support forms of validation and facilitate insight into the knowledge stored in those nets. What about simplicity of form?   Many rule processing technologies do indeed use a very simple form (‘If...Then’, ‘When...Do’, etc.)   However, it is a fundamental mistake to equate simplicity of form with simplicity of function.   It is absolutely mistaken to suggest that simplicity of form is a barrier to the efficient handling of complexity.   There are countless real-world examples which serve to disprove that notion.   Indeed, simplicity of form is often the key to handling complexity. Does rule processing offer a ‘one size fits all’. No, of course not.   No serious commentator suggests it does.   Does the design and management of large knowledge bases, expressed as rules, become difficult?   Yes, it can do, but that is true of any large knowledge base, regardless of the form in which knowledge is expressed.   The measure of complexity is not a function of rule set size or rule form.  It tends to be correlated more strongly with the size of the ‘problem space’ (‘search space’) which is something quite different.   Analysis of the problem space and the algorithms we use to search through that space are, of course, the very things we use to derive objective measures of the complexity of a given problem. This is basic computer science and common practice. Sailing a Dreadnaught through the sea of information technology and lobbing shells at some of the islands we encounter along the way does no one any good.   Building bridges and causeways between islands so that the inhabitants can collaborate in open discourse offers hope of real progress.

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• Trace File Source Adapter

  The Trace File Source adapter is a useful addition to your SSIS toolbox.  It allows you to read 2005 and 2008 profiler traces stored as .trc files and read them into the Data Flow.  From there you can perform filtering and analysis using the power of SSIS. There is no need for a SQL Server connection this just uses the trace file. Example Usages Cache warming for SQL Server Analysis Services Reading the flight recorder Find out the longest running queries on a server Analyze statements for CPU, memory by user or some other criteria you choose Properties The Trace File Source adapter has two properties, both of which combine to control the source trace file that is read at runtime. SQL Server 2005 and SQL Server 2008 trace files are supported for both the Database Engine (SQL Server) and Analysis Services. The properties are managed by the Editor form or can be set directly from the Properties Grid in Visual Studio. Property Type Description AccessMode Enumeration This property determines how the Filename property is interpreted. The values available are: DirectInput Variable Filename String This property holds the path for trace file to load (*.trc). The value is either a full path, or the name of a variable which contains the full path to the trace file, depending on the AccessMode property. Trace Column Definition Hopefully the majority of you can skip this section entirely, but if you encounter some problems processing a trace file this may explain it and allow you to fix the problem. The component is built upon the trace management API provided by Microsoft. Unfortunately API methods that expose the schema of a trace file have known issues and are unreliable, put simply the data often differs from what was specified. To overcome these limitations the component uses  some simple XML files. These files enable the trace column data types and sizing attributes to be overridden. For example SQL Server Profiler or TMO generated structures define EventClass as an integer, but the real value is a string. TraceDataColumnsSQL.xml  - SQL Server Database Engine Trace Columns TraceDataColumnsAS.xml    - SQL Server Analysis Services Trace Columns The files can be found in the %ProgramFiles%\Microsoft SQL Server\100\DTS\PipelineComponents folder, e.g. "C:\Program Files\Microsoft SQL Server\100\DTS\PipelineComponents\TraceDataColumnsSQL.xml" "C:\Program Files\Microsoft SQL Server\100\DTS\PipelineComponents\TraceDataColumnsAS.xml" If at runtime the component encounters a type conversion or sizing error it is most likely due to a discrepancy between the column definition as reported by the API and the actual value encountered. Whilst most common issues have already been fixed through these files we have implemented specific exception traps to direct you to the files to enable you to fix any further issues due to different usage or data scenarios that we have not tested. An example error that you can fix through these files is shown below. Buffer exception writing value to column 'Column Name'. The string value is 999 characters in length, the column is only 111. Columns can be overridden by the TraceDataColumns XML files in "C:\Program Files\Microsoft SQL Server\100\DTS\PipelineComponents\TraceDataColumnsAS.xml". Installation The component is provided as an MSI file which you can download and run to install it. This simply places the files on disk in the correct locations and also installs the assemblies in the Global Assembly Cache as per Microsoft’s recommendations. You may need to restart the SQL Server Integration Services service, as this caches information about what components are installed, as well as restarting any open instances of Business Intelligence Development Studio (BIDS) / Visual Studio that you may be using to build your SSIS packages. Finally you will have to add the transformation to the Visual Studio toolbox manually. Right-click the toolbox, and select Choose Items.... Select the SSIS Data Flow Items tab, and then check the Trace File Source transformation in the Choose Toolbox Items window. This process has been described in detail in the related FAQ entry for How do I install a task or transform component? We recommend you follow best practice and apply the current Microsoft SQL Server Service pack to your SQL Server servers and workstations. Please note that the Microsoft Trace classes used in the component are not supported on 64-bit platforms. To use the Trace File Source on a 64-bit host you need to ensure you have the 32-bit (x86) tools available, and the way you execute your package is setup to use them, please see the help topic 64-bit Considerations for Integration Services for more details. Downloads Trace Sources for SQL Server 2005 -- Trace Sources for SQL Server 2008 Version History SQL Server 2008 Version 2.0.0.382 - SQL Sever 2008 public release. (9 Apr 2009) SQL Server 2005 Version 1.0.0.321 - SQL Server 2005 public release. (18 Nov 2008) -- Screenshots

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• Rob Blackwell on interoperability and Azure

  - by Eric Nelson

  At QCon in March we had a sample Azure application implemented in both Java and Ruby to demonstrate that the Windows Azure Platform is not just about .NET. The following is an interesting interview with Rob Blackwell, the R&D director of the partner who implemented the application. UK Interoperability Team Interviews Rob Blackwell, R&D Director at Active Web Solutions. Is Microsoft taking interoperability seriously? Yes. In the past, I think Microsoft has, quite rightly come in for criticism, but architects and developers should look at this again. The Interoperability Bridges site (http://www.interoperabilitybridges.com/ ) shows a wide range of projects that allow interoperability from Java, Ruby and PHP for example. The Windows Azure platform has been architected with interoperable APIs in mind. It's straightforward to access the various storage facilities from just about any language or platform. Azure compute is capable of running more than just C# applications! Why is interoperability important to you? My company provides consultancy and bespoke development services. We're a Microsoft Gold Partner, but we live in the real world where companies have a mix of technologies provided by a variety of vendors. When developing an enterprise software solution, you rarely have a completely blank canvas. We often see integration scenarios where we need to exchange data with legacy systems. It's not unusual to see modern Silverlight applications being built on top of Java or Mainframe based back ends. Could you give us some examples of where interoperability has been important for your projects? We developed an innovative Sea Safety system for the RNLI Lifeboats here in the UK. Commercial Fishing is one of the most dangerous professions and we helped developed the MOB Guardian System which uses satellite technology and man overboard devices to raise the alarm when a fisherman gets into trouble. The solution is implemented in .NET running on Windows, but without interoperable standards, it would have been impossible to communicate with the satellite gateway technology. For more information, please see the case study: http://www.microsoft.com/casestudies/Case_Study_Detail.aspx?CaseStudyID=4000005892 More recently, we were asked to build a web site to accompany the QCon 2010 conference in London to help demonstrate and promote interoperability. We built the site using Java and Restlet and hosted it in Windows Azure Compute. The site accepts feedback from visitors and all the data is stored in Windows Azure Storage. We also ported the application to Ruby on Rails for demonstration purposes. Visitors to the stand were surprised that this was even possible. Why should Java developers be interested in Windows Azure? Windows Azure Storage consists of Blobs, Queues and Tables. The storage is scalable, durable, secure and cost-effective. Using the WindowsAzure4j library, it's easy to use, and takes just a few lines of code. If you are writing an application with large data storage requirements, or you want an offsite backup, it makes a lot of sense. Running Java applications in Azure Compute is straightforward with tools like the Tomcat Solution Accelerator (http://code.msdn.microsoft.com/winazuretomcat )and AzureRunMe (http://azurerunme.codeplex.com/ ). The Windows Azure AppFabric Service Bus can also be used to connect heterogeneous systems running on different networks and in different data centres. How can The Service Bus be considered an interoperability solution? I think that the Windows Azure AppFabric Service Bus is one of Microsoft’s best kept secrets. Think of it as “a globally scalable application plumbing kit in the sky”. If you have used Enterprise Service Buses before, you’ll be familiar with the concept. Applications can connect to the service bus to securely exchange data – these can be point to point or multicast links. With the AppFabric Service Bus, the applications can exist anywhere that has access to the Internet and the connections can traverse firewalls. This makes it easy to extend or scale your application or reach out to other networks and technologies. For example, let’s say you have a SQL Server database running on premises and you want to expose the data to a Java application running in the cloud. You could set up a point to point Service Bus connection and use JDBC. Traditionally this would have been difficult or impossible without punching holes in firewalls and compromising security. Rob Blackwell is R&D Director at Active Web Solutions, www.aws.net , a Microsoft Gold Partner specialising in leading edge software solutions. He is an occasional writer and conference speaker and blogs at www.robblackwell.org.uk Related Links: UK Azure Online Community – join today. UK Windows Azure Site Start working with Windows Azure

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• SQL SERVER – SSMS: Memory Usage By Memory Optimized Objects Report

  - by Pinal Dave

  At conferences and at speaking engagements at the local UG, there is one question that keeps on coming which I wish were never asked. The question around, “Why is SQL Server using up all the memory and not releasing even when idle?” Well, the answer can be long and with the release of SQL Server 2014, this got even more complicated. This release of SQL Server 2014 has the option of introducing In-Memory OLTP which is completely new concept and our dependency on memory has increased multifold. In reality, nothing much changes but we have memory optimized objects (Tables and Stored Procedures) additional which are residing completely in memory and improving performance. As a DBA, it is humanly impossible to get a hang of all the innovations and the new features introduced in the next version. So today’s blog is around the report added to SSMS which gives a high level view of this new feature addition. This reports is available only from SQL Server 2014 onwards because the feature was introduced in SQL Server 2014. Earlier versions of SQL Server Management Studio would not show the report in the list. If we try to launch the report on the database which is not having In-Memory File group defined, then we would see the message in report. To demonstrate, I have created new fresh database called MemoryOptimizedDB with no special file group. Here is the query used to identify whether a database has memory-optimized file group or not. SELECT TOP(1) 1 FROM sys.filegroups FG WHERE FG.[type] = 'FX' Once we add filegroup using below command, we would see different version of report. USE [master] GO ALTER DATABASE [MemoryOptimizedDB] ADD FILEGROUP [IMO_FG] CONTAINS MEMORY_OPTIMIZED_DATA GO The report is still empty because we have not defined any Memory Optimized table in the database.  Total allocated size is shown as 0 MB. Now, let’s add the folder location into the filegroup and also created few in-memory tables. We have used the nomenclature of IMO to denote “InMemory Optimized” objects. USE [master] GO ALTER DATABASE [MemoryOptimizedDB] ADD FILE ( NAME = N'MemoryOptimizedDB_IMO', FILENAME = N'E:\Program Files\Microsoft SQL Server\MSSQL12.SQL2014\MSSQL\DATA\MemoryOptimizedDB_IMO') TO FILEGROUP [IMO_FG] GO You may have to change the path based on your SQL Server configuration. Below is the script to create the table. USE MemoryOptimizedDB GO --Drop table if it already exists. IF OBJECT_ID('dbo.SQLAuthority','U') IS NOT NULL DROP TABLE dbo.SQLAuthority GO CREATE TABLE dbo.SQLAuthority ( ID INT IDENTITY NOT NULL, Name CHAR(500)  COLLATE Latin1_General_100_BIN2 NOT NULL DEFAULT 'Pinal', CONSTRAINT PK_SQLAuthority_ID PRIMARY KEY NONCLUSTERED (ID), INDEX hash_index_sample_memoryoptimizedtable_c2 HASH (Name) WITH (BUCKET_COUNT = 131072) ) WITH (MEMORY_OPTIMIZED = ON, DURABILITY = SCHEMA_AND_DATA) GO As soon as above script is executed, table and index both are created. If we run the report again, we would see something like below. Notice that table memory is zero but index is using memory. This is due to the fact that hash index needs memory to manage the buckets created. So even if table is empty, index would consume memory. More about the internals of how In-Memory indexes and tables work will be reserved for future posts. Now, use below script to populate the table with 10000 rows INSERT INTO SQLAuthority VALUES (DEFAULT) GO 10000 Here is the same report after inserting 1000 rows into our InMemory table.    There are total three sections in the whole report. Total Memory consumed by In-Memory Objects Pie chart showing memory distribution based on type of consumer – table, index and system. Details of memory usage by each table. The information about all three is taken from one single DMV, sys.dm_db_xtp_table_memory_stats This DMV contains memory usage statistics for both user and system In-Memory tables. If we query the DMV and look at data, we can easily notice that the system tables have negative object IDs.  So, to look at user table memory usage, below is the over-simplified version of query. USE MemoryOptimizedDB GO SELECT OBJECT_NAME(OBJECT_ID), * FROM sys.dm_db_xtp_table_memory_stats WHERE OBJECT_ID > 0 GO This report would help DBA to identify which in-memory object taking lot of memory which can be used as a pointer for designing solution. I am sure in future we will discuss at lengths the whole concept of In-Memory tables in detail over this blog. To read more about In-Memory OLTP, have a look at In-Memory OLTP Series at Balmukund’s Blog. Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Server Management Studio, SQL Tips and Tricks, T SQL Tagged: SQL Memory, SQL Reports

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• SQL SERVER – Beginning of SQL Server Architecture – Terminology – Guest Post

  - by pinaldave

  SQL Server Architecture is a very deep subject. Covering it in a single post is an almost impossible task. However, this subject is very popular topic among beginners and advanced users.  I have requested my friend Anil Kumar who is expert in SQL Domain to help me write  a simple post about Beginning SQL Server Architecture. As stated earlier this subject is very deep subject and in this first article series he has covered basic terminologies. In future article he will explore the subject further down. Anil Kumar Yadav is Trainer, SQL Domain, Koenig Solutions. Koenig is a premier IT training firm that provides several IT certifications, such as Oracle 11g, Server+, RHCA, SQL Server Training, Prince2 Foundation etc. In this Article we will discuss about MS SQL Server architecture. The major components of SQL Server are: Relational Engine Storage Engine SQL OS Now we will discuss and understand each one of them. 1) Relational Engine: Also called as the query processor, Relational Engine includes the components of SQL Server that determine what your query exactly needs to do and the best way to do it. It manages the execution of queries as it requests data from the storage engine and processes the results returned. Different Tasks of Relational Engine: Query Processing Memory Management Thread and Task Management Buffer Management Distributed Query Processing 2) Storage Engine: Storage Engine is responsible for storage and retrieval of the data on to the storage system (Disk, SAN etc.). to understand more, let’s focus on the following diagram. When we talk about any database in SQL server, there are 2 types of files that are created at the disk level – Data file and Log file. Data file physically stores the data in data pages. Log files that are also known as write ahead logs, are used for storing transactions performed on the database. Let’s understand data file and log file in more details: Data File: Data File stores data in the form of Data Page (8KB) and these data pages are logically organized in extents. Extents: Extents are logical units in the database. They are a combination of 8 data pages i.e. 64 KB forms an extent. Extents can be of two types, Mixed and Uniform. Mixed extents hold different types of pages like index, System, Object data etc. On the other hand, Uniform extents are dedicated to only one type. Pages: As we should know what type of data pages can be stored in SQL Server, below mentioned are some of them: Data Page: It holds the data entered by the user but not the data which is of type text, ntext, nvarchar(max), varchar(max), varbinary(max), image and xml data. Index: It stores the index entries. Text/Image: It stores LOB ( Large Object data) like text, ntext, varchar(max), nvarchar(max),  varbinary(max), image and xml data. GAM & SGAM (Global Allocation Map & Shared Global Allocation Map): They are used for saving information related to the allocation of extents. PFS (Page Free Space): Information related to page allocation and unused space available on pages. IAM (Index Allocation Map): Information pertaining to extents that are used by a table or index per allocation unit. BCM (Bulk Changed Map): Keeps information about the extents changed in a Bulk Operation. DCM (Differential Change Map): This is the information of extents that have modified since the last BACKUP DATABASE statement as per allocation unit. Log File: It also known as write ahead log. It stores modification to the database (DML and DDL). Sufficient information is logged to be able to: Roll back transactions if requested Recover the database in case of failure Write Ahead Logging is used to create log entries Transaction logs are written in chronological order in a circular way Truncation policy for logs is based on the recovery model SQL OS: This lies between the host machine (Windows OS) and SQL Server. All the activities performed on database engine are taken care of by SQL OS. It is a highly configurable operating system with powerful API (application programming interface), enabling automatic locality and advanced parallelism. SQL OS provides various operating system services, such as memory management deals with buffer pool, log buffer and deadlock detection using the blocking and locking structure. Other services include exception handling, hosting for external components like Common Language Runtime, CLR etc. I guess this brief article gives you an idea about the various terminologies used related to SQL Server Architecture. In future articles we will explore them further. Guest Author  The author of the article is Anil Kumar Yadav is Trainer, SQL Domain, Koenig Solutions. Koenig is a premier IT training firm that provides several IT certifications, such as Oracle 11g, Server+, RHCA, SQL Server Training, Prince2 Foundation etc. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Security, SQL Server, SQL Tips and Tricks, SQL Training, T SQL, Technology

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• Protecting offline IRM rights and the error "Unable to Connect to Offline database"

  - by Simon Thorpe

  One of the most common problems I get asked about Oracle IRM is in relation to the error message "Unable to Connect to Offline database". This error message is a result of how Oracle IRM is protecting the cached rights on the local machine and if that cache has become invalid in anyway, this error is thrown. Offline rights and security First we need to understand how Oracle IRM handles offline use. The way it is implemented is one of the main reasons why Oracle IRM is the leading document security solution and demonstrates our methodology to ensure that solutions address both security and usability and puts the balance of these two in your control. Each classification has a set of predefined roles that the manager of the classification can assign to users. Each role has an offline period which determines the amount of time a user can access content without having to communicate with the IRM server. By default for the context model, which is the classification system that ships out of the box with Oracle IRM, the offline period for each role is 3 days. This is easily changed however and can be as low as under an hour to as long as years. It is also possible to switch off the ability to access content offline which can be useful when content is very sensitive and requires a tight leash. So when a user is online, transparently in the background, the Oracle IRM Desktop communicates with the server and updates the users rights and offline periods. This transparent synchronization period is determined by the server and communicated to all IRM Desktops and allows for users rights to be kept up to date without their intervention. This allows us to support some very important scenarios which are key to a successful IRM solution. A user doesn't have to make any decision when going offline, they simply unplug their laptop and they already have their offline periods synchronized to the maximum values. Any solution that requires a user to make a decision at the point of going offline isn't going to work because people forget to do this and will therefore be unable to legitimately access their content offline. If your rights change to REMOVE your access to content, this also happens in the background. This is very useful when someone has an offline duration of a week and they happen to make a connection to the internet 3 days into that offline period, the Oracle IRM Desktop detects this online state and automatically updates all rights for the user. This means the business risk is reduced when setting long offline periods, because of the daily transparent sync, you can reflect changes as soon as the user is online. Of course, if they choose not to come online at all during that week offline period, you cannot effect change, but you take that risk in giving the 7 day offline period in the first place. If you are added to a NEW classification during the day, this will automatically be synchronized without the user even having to open a piece of content secured against that classification. This is very important, consider the scenario where a senior executive downloads all their email but doesn't open any of it. Disconnects the laptop and then gets on a plane. During the flight they attempt to open a document attached to a downloaded email which has been secured against an IRM classification the user was not even aware they had access to. Because their new role in this classification was automatically synchronized their experience is a good one and the document opens. More information on how the Oracle IRM classification model works can be found in this article by Martin Abrahams. So what about problems accessing the offline rights database? So onto the core issue... when these rights are cached to your machine they are stored in an encrypted database. The encryption of this offline database is keyed to the instance of the installation of the IRM Desktop and the Windows user account. Why? Well what you do not want to happen is for someone to get their rights for content and then copy these files across hundreds of other machines, therefore getting access to sensitive content across many environments. The IRM server has a setting which controls how many times you can cache these rights on unique machines. This is because people typically access IRM content on more than one computer. Their work desktop, a laptop and often a home computer. So Oracle IRM allows for the usability of caching rights on more than one computer whilst retaining strong security over this cache. So what happens if these files are corrupted in someway? That's when you will see the error, Unable to Connect to Offline database. The most common instance of seeing this is when you are using virtual machines and copy them from one computer to the next. The virtual machine software, VMWare Workstation for example, makes changes to the unique information of that virtual machine and as such invalidates the offline database. How do you solve the problem? Resolution is however simple. You just delete all of the offline database files on the machine and they will be recreated with working encryption when the Oracle IRM Desktop next starts. However this does mean that the IRM server will think you have your rights cached to more than one computer and you will need to rerequest your rights, even though you are only going to be accessing them on one. Because it still thinks the old cache is valid. So be aware, it is good practice to increase the server limit from the default of 1 to say 3 or 4. This is done using the Enterprise Manager instance of IRM. So to delete these offline files I have a simple .bat file you can use; Download DeleteOfflineDBs.bat Note that this uses pskillto stop the irmBackground.exe from running. This is part of the IRM Desktop and holds open a lock to the offline database. Either kill this from task manager or use pskillas part of the script.

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• Pre-filtering and shaping OData feeds using WCF Data Services and the Entity Framework - Part 2

  - by rajbk

  In the previous post, you saw how to create an OData feed and pre-filter the data. In this post, we will see how to shape the data. A sample project is attached at the bottom of this post. Pre-filtering and shaping OData feeds using WCF Data Services and the Entity Framework - Part 1 Shaping the feed The Product feed we created earlier returns too much information about our products. Let’s change this so that only the following properties are returned – ProductID, ProductName, QuantityPerUnit, UnitPrice, UnitsInStock. We also want to return only Products that are not discontinued.  Splitting the Entity To shape our data according to the requirements above, we are going to split our Product Entity into two and expose one through the feed. The exposed entity will contain only the properties listed above. We will use the other Entity in our Query Interceptor to pre-filter the data so that discontinued products are not returned. Go to the design surface for the Entity Model and make a copy of the Product entity. A “Product1” Entity gets created.   Rename Product1 to ProductDetail. Right click on the Product entity and select “Add Association” Make a one to one association between Product and ProductDetails.   Keep only the properties we wish to expose on the Product entity and delete all other properties on it (see diagram below). You delete a property on an Entity by right clicking on the property and selecting “delete”. Keep the ProductID on the ProductDetail. Delete any other property on the ProductDetail entity that is already present in the Product entity. Your design surface should look like below:    Mapping Entity to Database Tables Right click on “ProductDetail” and go to “Table Mapping”   Add a mapping to the “Products” table in the Mapping Details.   After mapping ProductDetail, you should see the following.   Add a referential constraint. Lets add a referential constraint which is similar to a referential integrity constraint in SQL. Double click on the Association between the Entities and add the constraint with “Principal” set to “Product”. Let us review what we did so far. We made a copy of the Product entity and called it ProductDetail We created a one to one association between these entities Excluding the ProductID, we made sure properties were not duplicated between these entities  We added a ProductDetail entity to Products table mapping (Entity to Database). We added a referential constraint between the entities. Lets build our project. We get the following error: ”'NortwindODataFeed.Product' does not contain a definition for 'Discontinued' and no extension method 'Discontinued' accepting a first argument of type 'NortwindODataFeed.Product' could be found …" The reason for this error is because our Product Entity no longer has a “Discontinued” property. We “moved” it to the ProductDetail entity since we want our Product Entity to contain only properties that will be exposed by our feed. Since we have a one to one association between the entities, we can easily rewrite our Query Interceptor like so: [QueryInterceptor("Products")] public Expression<Func<Product, bool>> OnReadProducts() { return o => o.ProductDetail.Discontinued == false; } Similarly, all “hidden” properties of the Product table are available to us internally (through the ProductDetail Entity) for any additional logic we wish to implement. Compile the project and view the feed. We see that the feed returns only the properties that were part of the requirement.   To see the data in JSON format, you have to create a request with the following request header Accept: application/json, text/javascript, */* (easy to do in jQuery) The result should look like this: { "d" : { "results": [ { "__metadata": { "uri": "http://localhost.:2576/DataService.svc/Products(1)", "type": "NorthwindModel.Product" }, "ProductID": 1, "ProductName": "Chai", "QuantityPerUnit": "10 boxes x 20 bags", "UnitPrice": "18.0000", "UnitsInStock": 39 }, { "__metadata": { "uri": "http://localhost.:2576/DataService.svc/Products(2)", "type": "NorthwindModel.Product" }, "ProductID": 2, "ProductName": "Chang", "QuantityPerUnit": "24 - 12 oz bottles", "UnitPrice": "19.0000", "UnitsInStock": 17 }, { ... ... If anyone has the $format operation working, please post a comment. It was not working for me at the time of writing this.  We have successfully pre-filtered our data to expose only products that have not been discontinued and shaped our data so that only certain properties of the Entity are exposed. Note that there are several other ways you could implement this like creating a QueryView, Stored Procedure or DefiningQuery. You have seen how easy it is to create an OData feed, shape the data and pre-filter it by hardly writing any code of your own. For more details on OData, Google it with your favorite search engine :-) Also check out the one of the most passionate persons I have ever met, Pablo Castro – the Architect of Aristoria WCF Data Services. Watch his MIX 2010 presentation titled “OData: There's a Feed for That” here. Download Sample Project for VS 2010 RTM NortwindODataFeed.zip

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• SQL SERVER – SSMS: Backup and Restore Events Report

  - by Pinal Dave

  A DBA wears multiple hats and in fact does more than what an eye can see. One of the core task of a DBA is to take backups. This looks so trivial that most developers shrug this off as the only activity a DBA might be doing. I have huge respect for DBA’s all around the world because even if they seem cool with all the scripting, automation, maintenance works round the clock to keep the business working almost 365 days 24×7, their worth is knowing that one day when the systems / HDD crashes and you have an important delivery to make. So these backup tasks / maintenance jobs that have been done come handy and are no more trivial as they might seem to be as considered by many. So the important question like: “When was the last backup taken?”, “How much time did the last backup take?”, “What type of backup was taken last?” etc are tricky questions and this report lands answers to the same in a jiffy. So the SSMS report, we are talking can be used to find backups and restore operation done for the selected database. Whenever we perform any backup or restore operation, the information is stored in the msdb database. This report can utilize that information and provide information about the size, time taken and also the file location for those operations. Here is how this report can be launched.   Once we launch this report, we can see 4 major sections shown as listed below. Average Time Taken For Backup Operations Successful Backup Operations Backup Operation Errors Successful Restore Operations Let us look at each section next. Average Time Taken For Backup Operations Information shown in “Average Time Taken For Backup Operations” section is taken from a backupset table in the msdb database. Here is the query and the expanded version of that particular section USE msdb; SELECT (ROW_NUMBER() OVER (ORDER BY t1.TYPE))%2 AS l1 ,       1 AS l2 ,       1 AS l3 ,       t1.TYPE AS [type] ,       (AVG(DATEDIFF(ss,backup_start_date, backup_finish_date)))/60.0 AS AverageBackupDuration FROM backupset t1 INNER JOIN sys.databases t3 ON ( t1.database_name = t3.name) WHERE t3.name = N'AdventureWorks2014' GROUP BY t1.TYPE ORDER BY t1.TYPE On my small database the time taken for differential backup was less than a minute, hence the value of zero is displayed. This is an important piece of backup operation which might help you in planning maintenance windows. Successful Backup Operations Here is the expanded version of this section.   This information is derived from various backup tracking tables from msdb database.  Here is the simplified version of the query which can be used separately as well. SELECT * FROM sys.databases t1 INNER JOIN backupset t3 ON (t3.database_name = t1.name) LEFT OUTER JOIN backupmediaset t5 ON ( t3.media_set_id = t5.media_set_id) LEFT OUTER JOIN backupmediafamily t6 ON ( t6.media_set_id = t5.media_set_id) WHERE (t1.name = N'AdventureWorks2014') ORDER BY backup_start_date DESC,t3.backup_set_id,t6.physical_device_name; The report does some calculations to show the data in a more readable format. For example, the backup size is shown in KB, MB or GB. I have expanded first row by clicking on (+) on “Device type” column. That has shown me the path of the physical backup file. Personally looking at this section, the Backup Size, Device Type and Backup Name are critical and are worth a note. As mentioned in the previous section, this section also has the Duration embedded inside it. Backup Operation Errors This section of the report gets data from default trace. You might wonder how. One of the event which is tracked by default trace is “ErrorLog”. This means that whatever message is written to errorlog gets written to default trace file as well. Interestingly, whenever there is a backup failure, an error message is written to ERRORLOG and hence default trace. This section takes advantage of that and shows the information. We can read below message under this section, which confirms above logic. No backup operations errors occurred for (AdventureWorks2014) database in the recent past or default trace is not enabled. Successful Restore Operations This section may not be very useful in production server (do you perform a restore of database?) but might be useful in the development and log shipping secondary environment, where we might be interested to see restore operations for a particular database. Here is the expanded version of the section. To fill this section of the report, I have restored the same backups which were taken to populate earlier sections. Here is the simplified version of the query used to populate this output. USE msdb; SELECT * FROM restorehistory t1 LEFT OUTER JOIN restorefile t2 ON ( t1.restore_history_id = t2.restore_history_id) LEFT OUTER JOIN backupset t3 ON ( t1.backup_set_id = t3.backup_set_id) WHERE t1.destination_database_name = N'AdventureWorks2014' ORDER BY restore_date DESC,  t1.restore_history_id,t2.destination_phys_name Have you ever looked at the backup strategy of your key databases? Are they in sync and do we have scope for improvements? Then this is the report to analyze after a week or month of maintenance plans running in your database. Do chime in with what are the strategies you are using in your environments. Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: PostADay, SQL, SQL Authority, SQL Backup and Restore, SQL Query, SQL Server, SQL Server Management Studio, SQL Tips and Tricks, T SQL Tagged: SQL Reports

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• Troubleshooting High-CPU Utilization for SQL Server

  - by Susantha Bathige

  The objective of this FAQ is to outline the basic steps in troubleshooting high CPU utilization on  a server hosting a SQL Server instance. The first and the most common step if you suspect high CPU utilization (or are alerted for it) is to login to the physical server and check the Windows Task Manager. The Performance tab will show the high utilization as shown below: Next, we need to determine which process is responsible for the high CPU consumption. The Processes tab of the Task Manager will show this information: Note that to see all processes you should select Show processes from all user. In this case, SQL Server (sqlserver.exe) is consuming 99% of the CPU (a normal benchmark for max CPU utilization is about 50-60%). Next we examine the scheduler data. Scheduler is a component of SQLOS which evenly distributes load amongst CPUs. The query below returns the important columns for CPU troubleshooting. Note – if your server is under severe stress and you are unable to login to SSMS, you can use another machine’s SSMS to login to the server through DAC – Dedicated Administrator Connection (see http://msdn.microsoft.com/en-us/library/ms189595.aspx for details on using DAC) SELECT scheduler_id ,cpu_id ,status ,runnable_tasks_count ,active_workers_count ,load_factor ,yield_count FROM sys.dm_os_schedulers WHERE scheduler_id See below for the BOL definitions for the above columns. scheduler_id – ID of the scheduler. All schedulers that are used to run regular queries have ID numbers less than 1048576. Those schedulers that have IDs greater than or equal to 1048576 are used internally by SQL Server, such as the dedicated administrator connection scheduler. cpu_id – ID of the CPU with which this scheduler is associated. status – Indicates the status of the scheduler. runnable_tasks_count – Number of workers, with tasks assigned to them that are waiting to be scheduled on the runnable queue. active_workers_count – Number of workers that are active. An active worker is never preemptive, must have an associated task, and is either running, runnable, or suspended. current_tasks_count - Number of current tasks that are associated with this scheduler. load_factor – Internal value that indicates the perceived load on this scheduler. yield_count – Internal value that is used to indicate progress on this scheduler.                                                                 Now to interpret the above data. There are four schedulers and each assigned to a different CPU. All the CPUs are ready to accept user queries as they all are ONLINE. There are 294 active tasks in the output as per the current_tasks_count column. This count indicates how many activities currently associated with the schedulers. When a  task is complete, this number is decremented. The 294 is quite a high figure and indicates all four schedulers are extremely busy. When a task is enqueued, the load_factor  value is incremented. This value is used to determine whether a new task should be put on this scheduler or another scheduler. The new task will be allocated to less loaded scheduler by SQLOS. The very high value of this column indicates all the schedulers have a high load. There are 268 runnable tasks which mean all these tasks are assigned a worker and waiting to be scheduled on the runnable queue.   The next step is  to identify which queries are demanding a lot of CPU time. The below query is useful for this purpose (note, in its current form,  it only shows the top 10 records). SELECT TOP 10 st.text  ,st.dbid  ,st.objectid  ,qs.total_worker_time  ,qs.last_worker_time  ,qp.query_plan FROM sys.dm_exec_query_stats qs CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) st CROSS APPLY sys.dm_exec_query_plan(qs.plan_handle) qp ORDER BY qs.total_worker_time DESC This query as total_worker_time as the measure of CPU load and is in descending order of the  total_worker_time to show the most expensive queries and their plans at the top:      Note the BOL definitions for the important columns: total_worker_time - Total amount of CPU time, in microseconds, that was consumed by executions of this plan since it was compiled. last_worker_time - CPU time, in microseconds, that was consumed the last time the plan was executed.   I re-ran the same query again after few seconds and was returned the below output. After few seconds the SP dbo.TestProc1 is shown in fourth place and once again the last_worker_time is the highest. This means the procedure TestProc1 consumes a CPU time continuously each time it executes.      In this case, the primary cause for high CPU utilization was a stored procedure. You can view the execution plan by clicking on query_plan column to investigate why this is causing a high CPU load. I have used SQL Server 2008 (SP1) to test all the queries used in this article.

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• Make a Drive Image Using an Ubuntu Live CD

  - by Trevor Bekolay

  Cloning a hard drive is useful, but what if you have to make several copies, or you just want to make a complete backup of a hard drive? Drive images let you put everything, and we mean everything, from your hard drive in one big file. With an Ubuntu Live CD, this is a simple process – the versatile tool dd can do this for us right out of the box. We’ve used dd to clone a hard drive before. Making a drive image is very similar, except instead of copying data from one hard drive to another, we copy from a hard drive to a file. Drive images are more flexible, as you can do what you please with the data once you’ve pulled it off the source drive. Your drive image is going to be a big file, depending on the size of your source drive – dd will copy every bit of it, even if there’s only one tiny file stored on the whole hard drive. So, to start, make sure you have a device connected to your computer that will be large enough to hold the drive image. Some ideas for places to store the drive image, and how to connect to them in an Ubuntu Live CD, can be found at this previous Live CD article. In this article, we’re going to make an image of a 1GB drive, and store it on another hard drive in the same PC. Note: always be cautious when using dd, as it’s very easy to completely wipe out a drive, as we will show later in this article. Creating a Drive Image Boot up into the Ubuntu Live CD environment. Since we’re going to store the drive image on a local hard drive, we first have to mount it. Click on Places and then the location that you want to store the image on – in our case, a 136GB internal drive. Open a terminal window (Applications > Accessories > Terminal) and navigate to the newly mounted drive. All mounted drives should be in /media, so we’ll use the command cd /media and then type the first few letters of our difficult-to-type drive, press tab to auto-complete the name, and switch to that directory. If you wish to place the drive image in a specific folder, then navigate to it now. We’ll just place our drive image in the root of our mounted drive. The next step is to determine the identifier for the drive you want to make an image of. In the terminal window, type in the command sudo fdisk -l Our 1GB drive is /dev/sda, so we make a note of that. Now we’ll use dd to make the image. The invocation is sudo dd if=/dev/sda of=./OldHD.img This means that we want to copy from the input file (“if”) /dev/sda (our source drive) to the output file (“of”) OldHD.img, which is located in the current working directory (that’s the “.” portion of the “of” string). It takes some time, but our image has been created…Let’s test to make sure it works. Drive Image Testing: Wiping the Drive Another interesting thing that dd can do is totally wipe out the data on a drive (a process we’ve covered before). The command for that is sudo dd if=/dev/urandom of=/dev/sda This takes some random data as input, and outputs it to our drive, /dev/sda. If we examine the drive now using sudo fdisk –l, we can see that the drive is, indeed, wiped. Drive Image Testing: Restoring the Drive Image We can restore our drive image with a call to dd that’s very similar to how we created the image. The only difference is that the image is going to be out input file, and the drive now our output file. The exact invocation is sudo dd if=./OldHD.img of=/dev/sda It takes a while, but when it’s finished, we can confirm with sudo fdisk –l that our drive is back to the way it used to be! Conclusion There are a lots of reasons to create a drive image, with backup being the most obvious. Fortunately, with dd creating a drive image only takes one line in a terminal window – if you’ve got an Ubuntu Live CD handy! Similar Articles Productive Geek Tips Reset Your Ubuntu Password Easily from the Live CDCreate a Bootable Ubuntu USB Flash Drive the Easy WayHow to Browse Without a Trace with an Ubuntu Live CDWipe, Delete, and Securely Destroy Your Hard Drive’s Data the Easy WayClone a Hard Drive Using an Ubuntu Live CD TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips HippoRemote Pro 2.2 Xobni Plus for Outlook All My Movies 5.9 CloudBerry Online Backup 1.5 for Windows Home Server Microsoft Office Web Apps Guide Know if Someone Accessed Your Facebook Account Shop for Music with Windows Media Player 12 Access Free Documentaries at BBC Documentaries Rent Cameras In Bulk At CameraRenter Download Songs From MySpace

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• Running Jetty under Windows Azure Using RoleEntryPoint in a Worker Role

  - by Shawn Cicoria

  This post is built upon the work of Mario Kosmiskas and David C. Chou’s prior postings – from here: http://blogs.msdn.com/b/mariok/archive/2011/01/05/deploying-java-applications-in-azure.aspx  http://blogs.msdn.com/b/dachou/archive/2010/03/21/run-java-with-jetty-in-windows-azure.aspx As Mario points out in his post, when you need to have more control over the process that starts, it generally is better left to a RoleEntryPoint capability that as of now, requires the use of a CLR based assembly that is deployed as part of the package to Azure. There were things I liked especially about Mario’s post – specifically, the ability to pull down the JRE and Jetty runtimes at role startup and instantiate the process using the extracted bits.  The way Mario initialized the java process (and Jetty) was to take advantage of a role startup task configured as part of the service definition.  This is a great quick way to kick off processes or tasks prior to your role entry point.  However, if you need access to service configuration values or role events, that’s where RoleEntryPoint comes in.  For this PoC sample I moved the logic for retrieving the bits for the jre and jetty to the worker roles OnStart – in addition to moving the process kickoff to the OnStart method.  The Run method at this point is there to loop and just report the status of the java process. Beyond just making things more parameterized, both Mario’s and David’s articles still form the essence of the approach. The solution that accompanies this post provides all the necessary .NET based Visual Studio project.  In addition, you’ll need: 1. Jetty 7 runtime http://www.eclipse.org/jetty/downloads.php 2. JRE http://www.oracle.com/technetwork/java/javase/downloads/index.html Once you have these the first step is to create archives (zips) of the distributions.  For this PoC, the structure of the archive requires that the root of the archive looks as follows: JRE6.zip jetty---.zip Upload the contents to a storage container (block blob), and for this example I used /archives as the location.  The service configuration has several settings that allow, which is the advantage of using RoleEntryPoint, the ability to provide these things via native configuration support from Azure in a worker role. Storage Explorer You can use development storage for testing this out – the zipped version of the solution is configured for development storage.  When you’re ready to deploy, you update the two settings – 1 for diagnostics and the other for the storage container where the /archives are going to be stored. <?xml version="1.0" encoding="utf-8"?> <ServiceConfiguration serviceName="HostedJetty" osFamily="2" osVersion="*"> <Role name="JettyWorker"> <Instances count="1" /> <ConfigurationSettings> <!--<Setting name="Microsoft.WindowsAzure.Plugins.Diagnostics.ConnectionString" value="DefaultEndpointsProtocol=https;AccountName=<accountName>;AccountKey=<accountKey>" />--> <Setting name="Microsoft.WindowsAzure.Plugins.Diagnostics.ConnectionString" value="UseDevelopmentStorage=true" /> <Setting name="JettyArchive" value="jetty-distribution-7.3.0.v20110203b.zip" /> <Setting name="StartRole" value="true" /> <Setting name="BlobContainer" value="archives" /> <Setting name="JreArchive" value="jre6.zip" /> <!--<Setting name="StorageCredentials" value="DefaultEndpointsProtocol=https;AccountName=<accountName>;AccountKey=<accountKey>"/>--> <Setting name="StorageCredentials" value="UseDevelopmentStorage=true" />   For interacting with Storage you can use several tools – one tool that I like is from the Windows Azure CAT team located here: http://appfabriccat.com/2011/02/exploring-windows-azure-storage-apis-by-building-a-storage-explorer-application/  and shown in the prior picture At runtime, during role initialization and startup, Azure will call into your RoleEntryPoint.  At that time the code will do a dynamic pull of the 2 archives and extract – using the Sharp Zip Lib <link> as Mario had demonstrated in his sample.  The only different here is the use of CLR code vs. PowerShell (which is really CLR, but that’s another discussion). At this point, once the 2 zips are extracted, the Role’s file system looks as follows: Worker Role approot From there, the OnStart method (which also does the download and unzip using a simple StorageHelper class) kicks off the Java path and now you have Java! Task Manager Jetty Sample Page A couple of things I’m working on to enhance this is to extract the jre and jetty bits not to the appRoot but to a resource location defined as part of the service definition. ServiceDefinition.csdef <?xml version="1.0" encoding="utf-8"?> <ServiceDefinition name="HostedJetty" xmlns="http://schemas.microsoft.com/ServiceHosting/2008/10/ServiceDefinition"> <WorkerRole name="JettyWorker"> <Imports> <Import moduleName="Diagnostics" /> <Import moduleName="RemoteAccess" /> <Import moduleName="RemoteForwarder" /> </Imports> <Endpoints> <InputEndpoint name="JettyPort" protocol="tcp" port="80" localPort="8080" /> </Endpoints> <LocalResources> <LocalStorage name="Archives" cleanOnRoleRecycle="false" sizeInMB="100" /> </LocalResources>   As the concept matures a bit, being able to update dynamically the content or jar files as part of a running java solution is something that is possible through continued enhancement of this simple model. The Visual Studio 2010 Solution is located here: HostingJavaSln_NDA.zip

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• Juniper Strategy, LLC is hiring SharePoint Developers&hellip;

  - by Mark Rackley

  Isn’t everybody these days? It seems as though there are definitely more jobs than qualified devs these days, but yes, we are looking for a few good devs to help round out our burgeoning SharePoint team. Juniper Strategy is located in the DC area, however we will consider remote devs for the right fit. This is your chance to get in on the ground floor of a bright company that truly “gets it” when it comes to SharePoint, Project Management, and Information Assurance. We need like-minded people who “get it”, enjoy it, and who are looking for more than just a job. We have government and commercial opportunities as well as our own internal product that has a bright future of its own. Our immediate needs are for SharePoint .NET developers, but feel free to submit your resume for us to keep on file as it looks as though we’ll need several people in the coming months. Please email us your resume and salary requirements to [email protected] Below are our official job postings. Thanks for stopping by, we look forward to  hearing from you. Senior SharePoint .NET Developer Senior developer will focus on design and coding of custom, end-to-end business process solutions within the SharePoint framework. Senior developer with the ability to serve as a senior developer/mentor and manage day-to-day development tasks. Work with business consultants and clients to gather requirements to prepare business functional specifications. Analyze and recommend technical/development alternative paths based on business functional specifications. For selected development path, prepare technical specification and build the solution. Assist project manager with defining development task schedule and level-of-effort. Lead technical solution deployment. Job Requirements Minimum of 7 years experience in agile development, with at least 3 years of SharePoint-related development experience (SPS, SharePoint 2007/2010, WSS2-4). Thorough understanding of and demonstrated experience in development under the SharePoint Object Model, with focus on the WSS 3.0 foundation (MOSS 2007 Standard/Enterprise, Project Server 2007). Experience with using multiple data sources/repositories for database CRUD activities, including relational databases, SAP, Oracle e-Business. Experience with designing and deploying performance-based solutions in SharePoint for business processes that involve a very large number of records. Experience designing dynamic dashboards and mashups with data from multiple sources (internal to SharePoint as well as from external sources). Experience designing custom forms to facilitate user data entry, both with and without leveraging Forms Services. Experience building custom web part solutions. Experience with designing custom solutions for processing underlying business logic requirements including, but not limited to, SQL stored procedures, C#/ASP.Net workflows/event handlers (including timer jobs) to support multi-tiered decision trees and associated computations. Ability to create complex solution packages for deployment (e.g., feature-stapled site definitions). Must have impeccable communication skills, both written and verbal. Seeking a "tinkerer"; proactive with a thirst for knowledge (and a sense of humor). A US Citizen is required, and need to be able to pass NAC/E-Verify. An active Secret clearance is preferred. Applicants must pass a skills assessment test. MCP/MCTS or comparable certification preferred. Salary & Travel Negotiable SharePoint Project Lead Define project task schedule, work breakdown structure and level-of-effort. Serve as principal liaison to the customer to manage deliverables and expectations. Day-to-day project and team management, including preparation and maintenance of project plans, budgets, and status reports. Prepare technical briefings and presentation decks, provide briefs to C-level stakeholders. Work with business consultants and clients to gather requirements to prepare business functional specifications. Analyze and recommend technical/development alternative paths based on business functional specifications. The SharePoint Project Lead will be working with SharePoint architects and system owners to perform requirements/gap analysis and develop the underlying functional specifications. Once we have functional specifications as close to "final" as possible, the Project Lead will be responsible for preparation of the associated technical specification/development blueprint, along with assistance in preparing IV&V/test plan materials with support from other team members. This person will also be responsible for day-to-day management of "developers", but is also expected to engage in development directly as needed.  Job Requirements Minimum 8 years of technology project management across the software development life-cycle, with a minimum of 3 years of project management relating specifically to SharePoint (SPS 2003, SharePoint2007/2010) and/or Project Server. Thorough understanding of and demonstrated experience in development under the SharePoint Object Model, with focus on the WSS 3.0 foundation (MOSS 2007 Standard/Enterprise, Project Server 2007). Ability to interact and collaborate effectively with team members and stakeholders of different skill sets, personalities and needs. General "development" skill set required is a fundamental understanding of MOSS 2007 Enterprise, SP1/SP2, from the top-level of skinning to the core of the SharePoint object model. Impeccable communication skills, both written and verbal, and a sense of humor are required. The projects will require being at a client site at least 50% of the time in Washington DC (NW DC) and Maryland (near Suitland). A US Citizen is required, and need to be able to pass NAC/E-Verify. An active Secret clearance is preferred. PMP certification, PgMP preferred. Salary & Travel Negotiable

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• MySQL Connector/Net 6.4.6 Maintenance Release has been released

  - by fernando

  MySQL Connector/Net 6.4.6, a new version of the all-managed .NET driver for MySQL has been released.  This is a maintenance release and is recommended for use in production environments. It is appropriate for use with MySQL server versions 5.0-5.6. This is intended to be the final release for Connector/NET 6.4. It is now available in source and binary form from http://dev.mysql.com/downloads/connector/net/#downloads and mirror sites (note that not all mirror sites may be up to date at this point-if you can't find this version on some mirror, please try again later or choose another download site.) The 6.4.6 version of MySQL Connector/Net brings the following fixes: - Fix for List.Contains generates a bunch of ORs instead of more efficient IN clause in   LINQ to Entities (Oracle bug #14016344, MySql bug #64934). - Fix for error when trying to change the name of an Index on the Indexes/Keys editor; along with this fix now users can change the Index type of a new Index which could not be done   in previous versions, and when changing the Index name the change is reflected on the list view at the left side of the Index/Keys editor (Oracle bug #13613801). - Fix for stored procedure call using only its name with EF code first (MySql bug #64999, Oracle bug #14008699). - Fix for performance issue in generated EF query: .NET StartsWith/Contains/EndsWith produces MySql's locate instead of Like (MySql bug #64935, Oracle bug #14009363). - Fix for script generated for code first contains wrong alter table and wrong declaration for byte[] (MySql bug #64216, Oracle bug #13900091). - Fix for Exception thrown when using cascade delete in an EDM Model-First in Entity Framework (Oracle bug #14008752, MySql bug #64779). - Fix for Session locking issue with MySqlSessionStateStore (MySql bug #63997, Oracble bug #13733054). - Fixed deleting a user profile using Profile provider (MySQL bug #64409, Oracle bug #13790123). - Fix for bug Cannot Create an Entity with a Key of Type String (MySQL bug #65289, Oracle bug #14540202). This fix checks if the type has a FixedLength facet set in order to create a char otherwise should create varchar, mediumtext or longtext types when using a String CLR type in Code First or Model First also tested in Database First. Unit tests added for Code First and ProviderManifest. - Fix for bug "CacheServerProperties can cause 'Packet too large' error" (MySQL Bug #66578 Orabug #14593547). - Fix for handling unnamed parameter in MySQLCommand. This fix allows the mysqlcommand to handle parameters without requiring naming (e.g. INSERT INTO Test (id,name) VALUES (?, ?) ) (MySQL Bug #66060, Oracle bug #14499549). - Fixed inheritance on Entity Framework Code First scenarios. Discriminator column is created using its correct type as varchar(128) (MySql bug #63920 and Oracle bug #13582335). - Fixed "Trying to customize column precision in Code First does not work" (MySql bug #65001, Oracle bug #14469048). - Fixed bug ASP.NET Membership database fails on MySql database UTF32 (MySQL bug #65144, Oracle bug #14495292). - Fix for MySqlCommand.LastInsertedId holding only 32 bit values (MySql bug #65452, Oracle bug #14171960) by changing   several internal declaration of lastinsertid from int to long. - Fixed "Decimal type should have digits at right of decimal point", now default is 2, but user's changes in   EDM designer are recognized (MySql bug #65127, Oracle bug #14474342). - Fix for NullReferenceException when saving an uninitialized row in Entity Framework (MySql bug #66066, Oracle bug #14479715). - Fix for error when calling RoleProvider.RemoveUserFromRole(): causes an exception due to a wrong table being used (MySql bug #65805, Oracle bug #14405338). - Fix for "Memory Leak on MySql.Data.MySqlClient.MySqlCommand", too many MemoryStream's instances created (MySql bug #65696, Oracle bug #14468204). - Small improvement on MySqlPoolManager CleanIdleConnections for better mysqlpoolmanager idlecleanuptimer at startup (MySql bug #66472 and Oracle bug #14652624). - Fix for bug TIMESTAMP values are mistakenly represented as DateTime with Kind = Local (Mysql bug #66964, Oracle bug #14740705). - Fix for bug Keyword not supported. Parameter name: AttachDbFilename (Mysql bug #66880, Oracle bug #14733472). - Added support to MySql script file to retrieve data when using "SHOW" statements. - Fix for Package Load Failure in Visual Studio 2005 (MySql bug #63073, Oracle bug #13491674). - Fix for bug "Unable to connect using IPv6 connections" (MySQL bug #67253, Oracle bug #14835718). - Added auto-generated values for Guid identity columns (MySql bug #67450, Oracle bug #15834176). - Fix for method FirstOrDefault not supported in some LINQ to Entities queries (MySql bug #67377, Oracle bug #15856964). The release is available to download at http://dev.mysql.com/downloads/connector/net/6.4.html Documentation ------------------------------------- You can view current Connector/Net documentation at http://dev.mysql.com/doc/refman/5.5/en/connector-net.html You can find our team blog at http://blogs.oracle.com/MySQLOnWindows. You can also post questions on our forums at http://forums.mysql.com/. Enjoy and thanks for the support!

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• SQL Developer Data Modeler v3.3 Early Adopter: Collaborative Design via Excel?

  - by thatjeffsmith

  As you may have heard last week, we have a new version of Oracle SQL Developer Data Modeler now available as an Early Adopter release. Version 3.3 has quite a few new features and I’ll be previewing them here. Today’s topic is our new Excel integration. It builds off of last week’s lesson: Search, so you may want to go read that first. They say it takes a village to raise a child. I say it takes a team to build a data model. You have your techie folks, your business folks, your in-betweeners, and your database geeks. Who gets to define how customers are represented and stored in your database? That data lives forever, so you better get it right from the beginning, or you’ll be living in a hacker’s paradise for years to come. Lots of good rantings, ravings, and advice on this topic in general on Karen Lopez’s (@datachick) blog. But let’s say you are the primary modeler on a project. You dutifully interview the business folks for their requirements. You sit down and start to model and think you’re pretty close. Now you need someone to confirm your assumptions and provide some feedback. Do you send your model over? Take a screenshot and blow it up on a whiteboard? Export to HTML and let them take a magic marker to their monitors? Or maybe you bite the bullet and install your modeling software on their desktops and take the hours or days required to train them up on how to use the the tool. Wouldn’t it be nice if they could just mark up their corrections in Excel and let you suck the updates back in? This is what we have started to build in Oracle SQL Developer Data Modeler. Let’s say you have a new table called ‘UT_STARTUPS.’ It looks a little something like this: A table in Oracle SQL Developer Data Modeler What I would like to do is have my team or co-worker review how I have defined those columns. Perhaps TIMESTAMP is overkill or maybe the column names themselves aren’t up to snuff. What I am going to do is now search for all the columns in my table, then export that to Excel. So do a search for UT_STARTUPS. Search, filter, then Report With the filter set to ‘Columns,’ if I do a report I’ll be only getting the columns that are resolving to my search term. So as long as my table name is unique in the model, I should get what I’m looking for. Here’s what I see when I click on the Report button: XLS or XLSX, either format is just fine I want to decide how the Column data is exported to Excel though, so I’m going to create a report template that I can use going forward. So click the ‘Manage’ button and setup a new template. I’m going to call mine ‘CollaborativeDevelopment.’ The templates allow me to define what properties are included in the reports. Once this is set, I’ll have the XLS file generated, and get to work Now let the Excel junkies do their stuff Note that not ALL of the report properties are update-able (yes, I made up a new word there) via Excel. We’ll have the full list of properties documented going forward, but in my Excel sheet, note that I can’t change the table name or the data types for the columns. I’m going to update some column names and supply ‘nice’ comments so the database users know what’s what. Here’s my input for the designer/architect/database dude: Be kind, please rew…use comments. Save the file, email it back to your modeler. Update the model from Excel That’s right, it’s a right mouse click from your model in the tree If everything goes right, you’ll see a nice confirmation message: It’s alive! Another to-do item on tap – making this dialog more informative. We’ll be showing exactly what in your model was updated from Excel. Let’s take another look at the model now Voila! Why are we doing this again? The goal is to reduce the number of round-trips from the modeler and the business process owner. One is used to working with Excel – why not allow them to mark up their changes in the tool they already know? This is an early adopter release and I anticipate this feature getting a good bit of tuning up before we release. Why don’t you download 3.3, give it a whirl, and let us know what you think?

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• doubleTwist is an iTunes Alternative that Supports Several Devices

  - by Mysticgeek

  There are a lot of iTunes users out there, but unfortunately you can’t use it with all of your portable devices. Today we take a look at doubleTwist, which allows you to sync your media with a multitude of portable devices and easily share it as well. Note: You can run doubleTwist on Windows or Mac, and here we take a look at the Windows version. Install & Setup doubleTwist Download and install doubleTwist using the defaults in the wizard… Installation takes several moments and you’ll see the progress while it finishes up. After installation is complete, sign up for an account if you don’t already have one. If you do have an account you can login right away. Enter in your username, email address, and password then click Sign Up.   You’ll get an confirmation email and need to activate the account before you can sign in. Once you’re all signed up, launch doubleTwist and you’ll be ready to start using it. doubleTwist Music The default music store is Amazon MP3 store which might appeal to those of you who are tired of the iTunes music store. A lot of times the music is cheaper and available at higher bit rates. You can start searching for music in the Amazon Music Store and previewing songs. To purchase anything though you will need to sign into your Amazon account.   Under Playlists it allows you to import your playlists from iTunes and Windows Media Player, which is a handy feature if you don’t want to set them up again. Of course you can play your songs through the music player on your desktop. Devices One of the coolest things about doubleTwist is that it supports a lot of different portable media devices including iPod, BlackBerry, Windows Mobile, Android, PSP, Smartphones, and much more. Unfortunately for Zune users…there isn’t any support for the Zune of Zune HD yet. Here we have a Creative Zen attached and can sync songs, pictures, and podcasts. An HTC-S620 Smartphone running Windows Mobile… Even a simple USB drive will be recognized and you can transfer your media to it as well.   Podcasts Finding your favorite audio and video podcasts is easy with the search feature. You can easily manage and subscribe to podcasts in the subscriptions section.   You can watch the video podcasts directly in doubleTwist. Sharing Media Also you can share digital media with your friends or add it to Flickr and YouTube. You can send any pictures, videos, or music in your library to other people by dragging it over. You can email users individually… Or access contacts from your Gmail and Yahoo accounts. There is a limit to how much you can send of video podcasts… only the first 10 minutes. The person you send it to will get a link in their email that points to your My Feed page on the doubleTwist site.   There they can access the media you sent…in this example it’s a video podcast but you can share any media. Other Features Under My Profile you can change your avatar and personal information.   In Preferences you can choose where media is stored, its startup actions, podcast subscriptions, and manage device syncing. Conclusion It’s still in beta stage so expect some bugs, but overall doubleTwist is a solid media player that is easy to use with a clean interface. It’s simple and doesn’t try to do too much so is fairly easy on system resources. The main annoyance is it tries to catalog all of your media out of the box. Which may be alright for some users with smaller media collections, but very irritating to advanced users with large collections. Also there is currently no support for the Zune, but according to their forums, it’s on the way. At the time of this writing it’s in public beta and can be downloaded for XP, Vista, Windows 7 (32 & 64 bit), and Mac OSX. If you’re looking for an iTunes alternative that works with several different portable devices, you might want to give DoubleTwist a try. Download DoubleTwist Public Beta See If Your Media Device is Supported by doubleTwist Similar Articles Productive Geek Tips MusicBee is a Fast and Powerful Music ManagerAvoid the Apple QuickTime Bloat with QT LiteBeginner Geek: Set Default Programs in Windows 7 and VistaBeginner Geeks: OpenOffice is a Free Cross Platform Alternative to MS OfficeManage Devices the Easy Way with Device Stage in Windows 7 TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 PCmover Professional Play Music in Chrome by Simply Dragging a File 15 Great Illustrations by Chow Hon Lam Easily Sync Files & Folders with Friends & Family Amazon Free Kindle for PC Download Stretch popurls.com with a Stylish Script (Firefox) OldTvShows.org – Find episodes of Hitchcock, Soaps, Game Shows and more

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• Personal search – the future of search

  - by jamiet

  [Four months ago I wrote a meandering blog post on another blogging site entitled Personal search – the future of search. The points I made therein are becoming more relevant to what I'm reading about and hoping to get involved in in the future so I'm re-posting here to a wider audience to hopefully get some more feedback and guage reaction to it. This has been prompted by the book Pull by David Siegel that is forming my current holiday reading (recommended to me by a commenter on my previous post Interesting things – Twitter annotations and your phone as a web server) and in particular by Siegel's notion of us all in the future having a personal online data vault.] My one-time colleague Paul Dawson recently wrote an article called The Future of Search and in it he proposed some interesting ideas. Some choice quotes: The growth of Chinese search giant Baidu is an indicator that fully localised and tailored content and offerings have great traction with local audiences This trend is already driving an increase in the use of specialist searches … Look at how Farecast is now integrated into Bing for example, or how Flightstats is now integrated into Google. Search does not necessarily have to begin with a keyword, but could start instead with a click or a touch. Take a look at Retrievr. Start drawing a picture in the box and see what happens. This is certainly search without the need for typing in keywords search technology has advanced greatly in recent years. The recent launch of Microsoft Live Labs’ Pivot has given us a taste of what we can expect to see in the future This really got me thinking about where search might go in the future and as my mind wandered I realised that as the amount of data that we collect about ourselves increases so too will the need and the desire to search it. The amount of electronic data that exists about each and every person is increasing and in the near future I fully expect that we are going to be able to store personal data such as: A history of our location (in fact Google Latitude already offers this facility) Recordings of all our phone conversations Health information history (weight, blood pressure etc…) Energy usage Spending history What films we watch, what radio stations we listen to Voting history Of course, most of this stuff is already stored somewhere but crucially we don’t have easy access to it. My utilities supplier knows how much electricity I’m using but if I want to know for myself I have to go and dig through my statements (assuming I have kept them). Similarly my doctor probably has ready access to all of my health records, my bank knows exactly what I have spent my money on, my cable supplier knows what I watch on TV and my mobile phone supplier probably knows exactly where I am and where I’ve been for the past few years. Strange then that none of this electronic information is available to me in a way that I can really make use of it; after all, its MY information. Its MY data. I created it. That is set to change. As technologies mature and customers become more technically cognizant they will demand more access to the data that companies hold about them. The companies themselves will realise the benefit that they derive from giving users what they want and will embrace ways of providing it. As a result the amount of data that we store about ourselves is going to increase exponentially and the desire to search and derive value from that data is going to grow with it; we are about to enter the era of the “personal datastore” and we will want, and need, to search through it in order to make sense of it all. Its interesting then that today when we think of search we think of search engines and yet in these personal datastores we’re referring to data that search engines can’t touch because WE own it and we (hopefully) choose to keep it private. Someone, I know not who, is going to lead in this space by making it easy for us to search our data and retrieve information that we have either forgotten or maybe didn’t even know in the first place. We will learn new things about ourselves and about our habits; we will share these findings with whomever we choose; we will compare what we discover with others; we will collaborate for mutual benefit and, most of all, we will educate ourselves as to how to live our lives better. Search will be the means to that end, it will enable us to make sense of the wealth of information that we will collect day in day out. The future of search is personal, why would we be interested in anything else? @Jamiet Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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• Oracle SQL Developer v3.2.1 Now Available

  - by thatjeffsmith

  Oracle SQL Developer version 3.2.1 is now available. I recommend that everyone now upgrade to this release. It features more than 200 bug fixes, tweaks, and polish applied to the 3.2 edition. The high profile bug fixes submitted by customers and users on our forums are listed in all their glory for your review. I want to highlight a few of the changes though, as I recognize many of you lack the time and/or patience to ‘read the docs.’ That would include me, which is why I enjoy writing these kinds of blog posts. I’m lazy – just like you! No more artificial line breaks between CREATE OR REPLACE and your PL/SQL In versions 3.2 and older, when you pull up your stored procedural objects in our editor, you would see a line break inserted between the CREATE OR REPLACE and then the body of your code. In version 3.2.1, we have removed the line break. 3.1 3.2.1 Trivia Did You Know? The database doesn’t store the ‘CREATE’ or ‘CREATE OR REPLACE’ bit of your PL/SQL code in the database. If we look at the USER_SOURCE view, we can see that the code begins with the object name. So the CREATE OR REPLACE bit is ‘artificial’ The intent is to give you the code necessary to recreate your object – and have it ‘compile’ into the database. We pretty much HAVE to add the ‘CREATE OR REPLACE.’ From now on it will appear inline with the first line of your code. Exporting Tables & Views When exporting data from your tables or views, previous versions of SQL Developer presented a 3 step wizard. It allows you to choose your columns and apply data filters for what is exported. This was kind of redundant. The grids already allowed you to select your columns and apply filters. Wouldn’t it be more intuitive AND efficient to just make the grids behave in a What You See Is What You Get (WYSIWYG) fashion? In version 3.2.1, that is exactly what will happen. The wizard now only has two steps and the grid will export the data and columns as defined in the visible grid. Let the grid properties define what is actually exported! And here is what is pasted into my worksheet: "BREWERY"|"CITY" "3 Brewers Restaurant Micro-Brewery"|"Toronto" "Amsterdam Brewing Co."|"Toronto" "Ball Brewing Company Ltd."|"Toronto" "Big Ram Brewing Company"|"Toronto" "Black Creek Historic Brewery"|"Toronto" "Black Oak Brewing"|"Toronto" "C'est What?"|"Toronto" "Cool Beer Brewing Company"|"Toronto" "Denison's Brewing"|"Toronto" "Duggan's Brewery"|"Toronto" "Feathers"|"Toronto" "Fermentations! - Danforth"|"Toronto" "Fermentations! - Mount Pleasant"|"Toronto" "Granite Brewery & Restaurant"|"Toronto" "Labatt's Breweries of Canada"|"Toronto" "Mill Street Brew Pub"|"Toronto" "Mill Street Brewery"|"Toronto" "Molson Breweries of Canada"|"Toronto" "Molson Brewery at Air Canada Centre"|"Toronto" "Pioneer Brewery Ltd."|"Toronto" "Post-Production Bistro"|"Toronto" "Rotterdam Brewing"|"Toronto" "Steam Whistle Brewing"|"Toronto" "Strand Brasserie"|"Toronto" "Upper Canada Brewing"|"Toronto" JUST what I wanted And One Last Thing Speaking of export, sometimes I want to send data to Excel. And sometimes I want to send multiple objects to Excel – to a single Excel file that is. In version 3.2.1 you can now do that. Let’s export the bulk of the HR schema to Excel, with each table going to it’s own workbook in the same worksheet. Select many tables, put them in in a single Excel worksheet If you try this in previous versions of SQL Developer it will just write the first table to the Excel file. This is one of the bugs we addressed in v3.2.1. Here is what the output Excel file looks like now: Many tables - Many workbooks in an Excel Worksheet I have a sneaky suspicion that this will be a frequently used feature going forward. Excel seems to be the cornerstone of many of our popular features. Imagine that!

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• Get your content off Blogger.com

  - by Daniel Moth

  Due to blogger.com deprecating FTP users I've decided to move my blog. When I think of the content of a blog, 4 items come to mind: blog posts, comments, binary files that the blog posts linked to (e.g. images, ZIP files) and the CSS+structure of the blog. 1. Binaries The binary files you used in your blog posts are sitting on your own web space, so really blogger.com is not involved with that. Nothing for you to do at this stage, I'll come back to these in another post. 2. CSS and structure In the best case this exists as a separate CSS file on your web space (so no action for now) or in a worst case, like me, your CSS is embedded with the HTML. In the latter case, simply navigate from you dashboard to "Template" then "Edit HTML" and copy paste the contents of the box. Save that locally in a txt file and we'll come back to that in another post. 3. Blog posts and Comments The blog posts and comments exist in all the HTML files on your own web space. Parsing HTML files to extract that can be painful, so it is easier to download the XML files from blogger's servers that contain all your blog posts and comments. 3.1 Single XML file, but incomplete The obvious thing to do is go into your dashboard "Settings" and under the "Basic" tab look at the top next to "Blog Tools". There is a link there to "Export blog" which downloads an XML file with both comments and posts. The problem with that is that it only contains 200 comments - if you have more than that, you will lose the surplus. Also, this XML file has a lot of noise, compared to the better solution described next. (note that a tool I will refer to in a future post deals with either kind of XML file) 3.2 Multiple XML files First you need to find your blog ID. In case you don't know what that is, navigate to the "Template" as described in section 2 above. You will find references to the blog id in the HTML there, but you can also see it as part of the URL in your browser: blogger.com/template-edit.g?blogID=YOUR_NUMERIC_ID. Mine is 7 digits. You can now navigate to these URLs to download the XML for your posts and comments respectively: blogger.com/feeds/YOUR_NUMERIC_ID/posts/default?max-results=500&start-index=1 blogger.com/feeds/YOUR_NUMERIC_ID/comments/default?max-results=200&start-index=1 Note that you can only get 500 posts at a time and only 200 comments at a time. To get more than that you have to change the URL and download the next batch. To get you started, to get the XML for the next 500 posts and next 200 comments respectively you’d have to use these URLs: blogger.com/feeds/YOUR_NUMERIC_ID/posts/default?max-results=500&start-index=501 blogger.com/feeds/YOUR_NUMERIC_ID/comments/default?max-results=200&start-index=201 ...and so on and so forth. Keep all the XML files in the same folder on your local machine (with nothing else in there). 4. Validating the XML aka editing older blog posts The XML files you just downloaded really contain HTML fragments inside for all your blog posts. If you are like me, your blog posts did not conform to XHTML so passing them to an XML parser (which is what we will want to do) will result in the XML parser choking. So the next step is to fix that. This can be no work at all for you, or a huge time sink or just a couple hours of pain (which was my case). The process I followed was to attempt to load the XML files using XmlDocument.Load and wait for the exception to be thrown from my code. The exception would point to the exact offending line and column which would help me fix the issue. Rather than fix it in the XML itself, I would go back and edit the offending blog post and fix it there - recommended! Then I'd repeat the cycle until the XML could be loaded in the XmlDocument. To give you an idea, some of the issues I encountered are: extra or missing quotes in img and href elements, direct usage of chevrons instead of encoding them as &lt;, missing closing tags, mismatched nested pairs of elements and capitalization of html elements. For a full list of things that may go wrong see this. 5. Opportunity for other changes I also found a few posts that did not have a category assigned so I fixed those too. I took the further opportunity to create new categories and tag some of my blog posts with that. Note that I did not remove/change categories of existing posts, but only added.   In an another post we'll see how to use the XML files you stored in the local folder… Comments about this post welcome at the original blog.

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• Html.RenderAction Failed when Validation Failed

  - by Shaun

  RenderAction method had been introduced when ASP.NET MVC 1.0 released in its MvcFuture assembly and then final announced along with the ASP.NET MVC 2.0. Similar as RenderPartial, the RenderAction can display some HTML markups which defined in a partial view in any parent views. But the RenderAction gives us the ability to populate the data from an action which may different from the action which populating the main view. For example, in Home/Index.aspx we can invoke the Html.RenderPartial(“MyPartialView”) but the data of MyPartialView must be populated by the Index action of the Home controller. If we need the MyPartialView to be shown in Product/Create.aspx we have to copy (or invoke) the relevant code from the Index action in Home controller to the Create action in the Product controller which is painful. But if we are using Html.RenderAction we can tell the ASP.NET MVC from which action/controller the data should be populated. in that way in the Home/Index.aspx and Product/Create.aspx views we just need to call Html.RenderAction(“CreateMyPartialView”, “MyPartialView”) so it will invoke the CreateMyPartialView action in MyPartialView controller regardless from which main view. But in my current project we found a bug when I implement a RenderAction method in the master page to show something that need to connect to the backend data center when the validation logic was failed on some pages. I created a sample application below.   Demo application I created an ASP.NET MVC 2 application and here I need to display the current date and time on the master page. I created an action in the Home controller named TimeSlot and stored the current date into ViewDate. This method was marked as HttpGet as it just retrieves some data instead of changing anything. 1: [HttpGet] 2: public ActionResult TimeSlot() 3: { 4: ViewData["timeslot"] = DateTime.Now; 5: return View("TimeSlot"); 6: } Next, I created a partial view under the Shared folder to display the date and time string. 1: <%@ Control Language="C#" Inherits="System.Web.Mvc.ViewUserControl<dynamic>" %> 2:  3: <span>Now: <% 1: : ViewData["timeslot"].ToString() %></span> Then at the master page I used Html.RenderAction to display it in front of the logon link. 1: <div id="logindisplay"> 2: <% 1: Html.RenderAction("TimeSlot", "Home"); %> 3:  4: <% 1: Html.RenderPartial("LogOnUserControl"); %> 5: </div> It’s fairly simple and works well when I navigated to any pages. But when I moved to the logon page and click the LogOn button without input anything in username and password the validation failed and my website crashed with the beautiful yellow page. (I really like its color style and fonts…)   How ASP.NET MVC executes Html.RenderAction In this example all other pages were rendered successful which means the ASP.NET MVC found the TimeSolt action under the Home controller except this situation. The only different is that when I clicked the LogOn button the browser send an HttpPost request to the server. Is that the reason of this bug? I created another action in Home controller with the same action name but for HttpPost. 1: [HttpPost] 2: [ActionName("TimeSlot")] 3: public ActionResult TimeSlot(object dummy) 4: { 5: return TimeSlot(); 6: } Or, I can use the AcceptVerbsAttribute on the TimeSlot action to let it allow both HttpGet and HttpPost. 1: [AcceptVerbs("GET", "POST")] 2: public ActionResult TimeSlot() 3: { 4: ViewData["timeslot"] = DateTime.Now; 5: return View("TimeSlot"); 6: } And then repeat what I did before and this time it worked well. Why we need the action for HttpPost here as it’s just data retrieving? That is because of how ASP.NET MVC executes the RenderAction method. In the source code of ASP.NET MVC we can see when proforming the RenderAction ASP.NET MVC creates a RequestContext instance from the current RequestContext and created a ChildActionMvcHandler instance which inherits from MvcHandler class. Then the ASP.NET MVC processes the handler through the HttpContext.Server.Execute method. That means it performs the action as a stand-alone request asynchronously and flush the result into the  TextWriter which is being used to render the current page. Since when I clicked the LogOn the request was in HttpPost so when ASP.NET MVC processed the ChildActionMvcHandler it would find the action which allow the current request method, which is HttpPost. Then our TimeSlot method in HttpGet would not be matched.   Summary In this post I introduced a bug in my currently developing project regards the new Html.RenderAction method provided within ASP.NET MVC 2 when processing a HttpPost request. In ASP.NET MVC world the underlying Http information became more important than in ASP.NET WebForm world. We need to pay more attention on which kind of request it currently created and how ASP.NET MVC processes.   Hope this helps, Shaun   All documents and related graphics, codes are provided "AS IS" without warranty of any kind. Copyright © Shaun Ziyan Xu. This work is licensed under the Creative Commons License.

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• MySQL Connector/Net 6.5.5 Maintenance Release has been released

  - by fernando

  MySQL Connector/Net 6.5.5, a new maintenance release of our 6.5 series, has been released.  This release is GA quality and is appropriate for use in production environments.  Please note that 6.6 is our latest driver series and is the recommended product for development. It is now available in source and binary form from http://dev.mysql.com/downloads/connector/net/#downloads and mirror sites (note that not all mirror sites may be up to date at this point-if you can't find this version on some mirror, please try again later or choose another download site.) The 6.5.5 version of MySQL Connector/Net brings the following fixes: - Fix for ArgumentNull exception when using Take().Count() in a LINQ to Entities query (bug MySql #64749, Oracle bug #13913047). - Fix for type varchar changed to bit when saving in Table Designer (Oracle bug #13916560). - Fix for error when trying to change the name of an Index on the Indexes/Keys editor; along with this fix now users can change the Index type of a new Index which could not be done   in previous versions, and when changing the Index name the change is reflected on the list view at the left side of the Index/Keys editor (Oracle bug #13613801). - Fix for stored procedure call using only its name with EF code first (MySql bug #64999, Oracle bug #14008699). - Fix for List.Contains generates a bunch of ORs instead of more efficient IN clause in   LINQ to Entities (Oracle bug #14016344, MySql bug #64934). - Fix for performance issue in generated EF query: .NET StartsWith/Contains/EndsWith produces MySql's locate instead of Like (MySql bug #64935, Oracle bug #14009363). - Fix for script generated for code first contains wrong alter table and wrong declaration for byte[] (MySql bug #64216, Oracle bug #13900091). - Fix and code contribution for bug Timed out sessions are removed without notification which allow to enable the Expired CallBack when Session Provider times out any session (bug MySql #62266 Oracle bug # 13354935) - Fix for Exception thrown when using cascade delete in an EDM Model-First in Entity Framework (Oracle bug #14008752, MySql bug #64779). - Fix for Session locking issue with MySqlSessionStateStore (MySql bug #63997, Oracble bug #13733054). - Fixed deleting a user profile using Profile provider (MySQL bug #64470, Oracle bug #13790123) - Fix for bug Cannot Create an Entity with a Key of Type String (MySQL bug #65289, Oracle bug #14540202). This fix checks if the type has a FixedLength facet set in order to create a char otherwise should create varchar, mediumtext or longtext types when using a String CLR type in Code First or Model First also tested in Database First. Unit tests added for Code First and ProviderManifest. - Fix for bug "CacheServerProperties can cause 'Packet too large' error". The issue was due to a missing reading of Max_allowed_packet server property when CacheServerProperties is in true, since the value was read only in the first connection but the following pooled connections had a wrong value causing a Packet too large error. Including also a unit test for this scenario. All unit test passed. MySQL Bug #66578 Orabug #14593547. - Fix for handling unnamed parameter in MySQLCommand. This fix allows the mysqlcommand to handle parameters without requiring naming (e.g. INSERT INTO Test (id,name) VALUES (?, ?) ) (MySQL Bug #66060, Oracle bug #14499549). - Fixed inheritance on Entity Framework Code First scenarios. Discriminator column is created using its correct type as varchar(128) (MySql bug #63920 and Oracle bug #13582335). - Fixed "Trying to customize column precision in Code First does not work" (MySql bug #65001, Oracle bug #14469048). - Fixed bug ASP.NET Membership database fails on MySql database UTF32 (MySQL bug #65144, Oracle bug #14495292). - Fix for MySqlCommand.LastInsertedId holding only 32 bit values (MySql bug #65452, Oracle bug #14171960) by changing   several internal declaration of lastinsertid from int to long. - Fixed "Decimal type should have digits at right of decimal point", now default is 2, but user's changes in   EDM designer are recognized (MySql bug #65127, Oracle bug #14474342). - Fix for NullReferenceException when saving an uninitialized row in Entity Framework (MySql bug #66066, Oracle bug #14479715). - Fix for error when calling RoleProvider.RemoveUserFromRole(): causes an exception due to a wrong table being used (MySql bug #65805, Oracle bug #14405338). - Fix for "Memory Leak on MySql.Data.MySqlClient.MySqlCommand", too many MemoryStream's instances created (MySql bug #65696, Oracle bug #14468204). - Added ANTLR attribution notice (Oracle bug #14379162). - Fixed Entity Framework + mysql connector/net in partial trust throws exceptions (MySql bug #65036, Oracle bug #14668820). - Added support in Parser for Datetime and Time types with precision when using Server 5.6 (No bug Number). - Small improvement on MySqlPoolManager CleanIdleConnections for better mysqlpoolmanager idlecleanuptimer at startup (MySql bug #66472 and Oracle bug #14652624). - Fix for bug TIMESTAMP values are mistakenly represented as DateTime with Kind = Local (Mysql bug #66964, Oracle bug #14740705). - Fix for bug Keyword not supported. Parameter name: AttachDbFilename (Mysql bug #66880, Oracle bug #14733472). - Added support to MySql script file to retrieve data when using "SHOW" statements. - Fix for Package Load Failure in Visual Studio 2005 (MySql bug #63073, Oracle bug #13491674). - Fix for bug "Unable to connect using IPv6 connections" (MySQL bug #67253, Oracle bug #14835718). - Added auto-generated values for Guid identity columns (MySql bug #67450, Oracle bug #15834176). - Fix for method FirstOrDefault not supported in some LINQ to Entities queries (MySql bug #67377, Oracle bug #15856964). The release is available to download at http://dev.mysql.com/downloads/connector/net/6.5.html Documentation ------------------------------------- You can view current Connector/Net documentation at http://dev.mysql.com/doc/refman/5.5/en/connector-net.html You can find our team blog at http://blogs.oracle.com/MySQLOnWindows. You can also post questions on our forums at http://forums.mysql.com/. Enjoy and thanks for the support! 

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• Personal search – the future of search

  - by jamiet

  [Four months ago I wrote a meandering blog post on another blogging site entitled Personal search – the future of search. The points I made therein are becoming more relevant to what I'm reading about and hoping to get involved in in the future so I'm re-posting here to a wider audience to hopefully get some more feedback and guage reaction to it. This has been prompted by the book Pull by David Siegel that is forming my current holiday reading (recommended to me by a commenter on my previous post Interesting things – Twitter annotations and your phone as a web server) and in particular by Siegel's notion of us all in the future having a personal online data vault.] My one-time colleague Paul Dawson recently wrote an article called The Future of Search and in it he proposed some interesting ideas. Some choice quotes: The growth of Chinese search giant Baidu is an indicator that fully localised and tailored content and offerings have great traction with local audiences This trend is already driving an increase in the use of specialist searches … Look at how Farecast is now integrated into Bing for example, or how Flightstats is now integrated into Google. Search does not necessarily have to begin with a keyword, but could start instead with a click or a touch. Take a look at Retrievr. Start drawing a picture in the box and see what happens. This is certainly search without the need for typing in keywords search technology has advanced greatly in recent years. The recent launch of Microsoft Live Labs’ Pivot has given us a taste of what we can expect to see in the future This really got me thinking about where search might go in the future and as my mind wandered I realised that as the amount of data that we collect about ourselves increases so too will the need and the desire to search it. The amount of electronic data that exists about each and every person is increasing and in the near future I fully expect that we are going to be able to store personal data such as: A history of our location (in fact Google Latitude already offers this facility) Recordings of all our phone conversations Health information history (weight, blood pressure etc…) Energy usage Spending history What films we watch, what radio stations we listen to Voting history Of course, most of this stuff is already stored somewhere but crucially we don’t have easy access to it. My utilities supplier knows how much electricity I’m using but if I want to know for myself I have to go and dig through my statements (assuming I have kept them). Similarly my doctor probably has ready access to all of my health records, my bank knows exactly what I have spent my money on, my cable supplier knows what I watch on TV and my mobile phone supplier probably knows exactly where I am and where I’ve been for the past few years. Strange then that none of this electronic information is available to me in a way that I can really make use of it; after all, its MY information. Its MY data. I created it. That is set to change. As technologies mature and customers become more technically cognizant they will demand more access to the data that companies hold about them. The companies themselves will realise the benefit that they derive from giving users what they want and will embrace ways of providing it. As a result the amount of data that we store about ourselves is going to increase exponentially and the desire to search and derive value from that data is going to grow with it; we are about to enter the era of the “personal datastore” and we will want, and need, to search through it in order to make sense of it all. Its interesting then that today when we think of search we think of search engines and yet in these personal datastores we’re referring to data that search engines can’t touch because WE own it and we (hopefully) choose to keep it private. Someone, I know not who, is going to lead in this space by making it easy for us to search our data and retrieve information that we have either forgotten or maybe didn’t even know in the first place. We will learn new things about ourselves and about our habits; we will share these findings with whomever we choose; we will compare what we discover with others; we will collaborate for mutual benefit and, most of all, we will educate ourselves as to how to live our lives better. Search will be the means to that end, it will enable us to make sense of the wealth of information that we will collect day in day out. The future of search is personal, why would we be interested in anything else? @Jamiet Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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• Do Not Optimize Without Measuring

  - by Alois Kraus

  Recently I had to do some performance work which included reading a lot of code. It is fascinating with what ideas people come up to solve a problem. Especially when there is no problem. When you look at other peoples code you will not be able to tell if it is well performing or not by reading it. You need to execute it with some sort of tracing or even better under a profiler. The first rule of the performance club is not to think and then to optimize but to measure, think and then optimize. The second rule is to do this do this in a loop to prevent slipping in bad things for too long into your code base. If you skip for some reason the measure step and optimize directly it is like changing the wave function in quantum mechanics. This has no observable effect in our world since it does represent only a probability distribution of all possible values. In quantum mechanics you need to let the wave function collapse to a single value. A collapsed wave function has therefore not many but one distinct value. This is what we physicists call a measurement. If you optimize your application without measuring it you are just changing the probability distribution of your potential performance values. Which performance your application actually has is still unknown. You only know that it will be within a specific range with a certain probability. As usual there are unlikely values within your distribution like a startup time of 20 minutes which should only happen once in 100 000 years. 100 000 years are a very short time when the first customer tries your heavily distributed networking application to run over a slow WIFI network… What is the point of this? Every programmer/architect has a mental performance model in his head. A model has always a set of explicit preconditions and a lot more implicit assumptions baked into it. When the model is good it will help you to think of good designs but it can also be the source of problems. In real world systems not all assumptions of your performance model (implicit or explicit) hold true any longer. The only way to connect your performance model and the real world is to measure it. In the WIFI example the model did assume a low latency high bandwidth LAN connection. If this assumption becomes wrong the system did have a drastic change in startup time. Lets look at a example. Lets assume we want to cache some expensive UI resource like fonts objects. For this undertaking we do create a Cache class with the UI themes we want to support. Since Fonts are expensive objects we do create it on demand the first time the theme is requested. A simple example of a Theme cache might look like this: using System; using System.Collections.Generic; using System.Drawing; struct Theme { public Color Color; public Font Font; } static class ThemeCache { static Dictionary<string, Theme> _Cache = new Dictionary<string, Theme> { {"Default", new Theme { Color = Color.AliceBlue }}, {"Theme12", new Theme { Color = Color.Aqua }}, }; public static Theme Get(string theme) { Theme cached = _Cache[theme]; if (cached.Font == null) { Console.WriteLine("Creating new font"); cached.Font = new Font("Arial", 8); } return cached; } } class Program { static void Main(string[] args) { Theme item = ThemeCache.Get("Theme12"); item = ThemeCache.Get("Theme12"); } } This cache does create font objects only once since on first retrieve of the Theme object the font is added to the Theme object. When we let the application run it should print “Creating new font” only once. Right? Wrong! The vigilant readers have spotted the issue already. The creator of this cache class wanted to get maximum performance. So he decided that the Theme object should be a value type (struct) to not put too much pressure on the garbage collector. The code Theme cached = _Cache[theme]; if (cached.Font == null) { Console.WriteLine("Creating new font"); cached.Font = new Font("Arial", 8); } does work with a copy of the value stored in the dictionary. This means we do mutate a copy of the Theme object and return it to our caller. But the original Theme object in the dictionary will have always null for the Font field! The solution is to change the declaration of struct Theme to class Theme or to update the theme object in the dictionary. Our cache as it is currently is actually a non caching cache. The funny thing was that I found out with a profiler by looking at which objects where finalized. I found way too many font objects to be finalized. After a bit debugging I found the allocation source for Font objects was this cache. Since this cache was there for years it means that the cache was never needed since I found no perf issue due to the creation of font objects. the cache was never profiled if it did bring any performance gain. to make the cache beneficial it needs to be accessed much more often. That was the story of the non caching cache. Next time I will write something something about measuring.

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