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  • I’m 99% confident that where you are matters

    - by ktegels
    It really has been a long time since I posted anything ofvalue here. Yes, a lot of that is by my own choice and some of you might bewondering if I’ve given up on SQL Server. No, haven’t, it remains a vital toolfor me. But I have become more of user of the product in last couple of yearsrather than somebody who is “internals guru.” To be frank, going from technicaltrainer to University professor has had a lot to do with that. I tend to caremuch less now about squeezing cycles out of execution times...(read more)

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  • ArchBeat Facebook Friday: Top 10 Shared Links - May 23-29, 2014

    - by OTN ArchBeat
    Among the 5,144 fans of the OTN ArchBeat Facebook Page the following Top 10 items were the most popular over the last seven days, May 23-29, 2014. GlassFish/Java EE Community Open Forum Today! | Reza Rahman Have questions about Glassfish? Java EE/GlassFish evangelist Reza Rahman has answers, and you can pick his brain tomorrow during an online forum organized by the London Glassfish User Group and C2B2. The event is free, but you must register in order to participate. Click the link for more information. Twitter Tuesday - Top 10 @ArchBeat Tweets - May 20-26, 2014 The top 10 @OTNArchBeat tweets for the week of May 20-26, 2014. Topics covered include ADF, Cloud, GoldenGate, KScope14, OBIEE, ODI, WebLogic, WebCenter, and more. FrameworkFolders Support has come to Oracle WebCenter Portal | JayJay Zheng Interested in working with Framework Folders in Oracle WebCenter Portal? Oracle ACE JayJay Zheng reviews the essentials. Video: Programming Best Practices - ADF Business Components | Frank Nimphius Frank Nimphius discusses best practices and recommendations for ADF Business Components in the latest video from ADF Architecture TV. Video: Kscope 2014 Preview: Data Modeling and Moving Meditation with Kent Graziano For your mind and your body! Oracle ACE Director Kent Graziano previews his Kscope 2014 data modeling presentations and the early morning Chi Gung sessions he will once again lead for Kscope attendees. OAG and OES Integration for Web API Security: skin and guts | Andre Correa A-Team architect Andre Correa's post examines a strategy for web API security that uses OAG (Oracle API Gateway) and OES (Oracle Entitlements Server). Getting Started with Coherence*Web in WebLogic Server 12.1.2 | Tim Middleton Solution architect Tim Middleton shows you how to configure Coherence*Web in WebLogic Server 12.1.2 and deploy a basic web application. SOA and Business Processes: You are the Process! Part of the 13-part "Industrial SOA" article series, this article looks at best practices for modeling and managing effective business processes. Authentication in Oracle Identity Federation/ IdP | Damien Carru Damien Carru discuss authentication when OIF acts as an IdP and how the server can be configured to use specific OAM Authentication Schemes to challenge the user. Caveats on Using WebLogic Server with JDK7 | JayJay Zheng Quick tech tips from Oracle ACE JayJay Zheng.

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  • Recommended workflows for Apache virtual hosts?

    - by craig zheng
    I do a lot of local web development work on my Ubuntu machine, and I'm constantly setting up virtual hosts in Apache. I don't need to do hard core server management, but I am getting tired of the repetitive process of manually adding config directives to files in /etc/apache2/sites-available/ and then updating the /etc/hosts file. Is there a more efficient or more automated way to do all this that I'm missing? Maybe something like rapache but that's actually working?

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  • Redirect users to internal webpage on first visit

    - by Sihan Zheng
    I have a lan of maybe 20 - 30 computers, and a Windows server 2003 server on hand (I can also run any x86 Linux distro). What I am trying to do, is to redirect users to a webserver inside the LAN the first time they visit certain domains. For example, the first time a user visits "google.com", they will be redirected to 192.168.1.2 (a webserver, where they will be shown a custom webpage), attempts after that will go to google. Pretty much what I am trying to do, is to provide a captive server like service, showing people a custom webpage the first time they try to access certain websites (but not others). I'm pretty flexable on how this can be done, as long as it works. Can you guys give me an idea on how to approach this problem? I am looking for (hopefully) a free solutions. Thanks

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  • Light Voip and IM server for small teams

    - by Sihan Zheng
    So I have a small group that would need a self hosted Im/voip and possibly video conferencing solution. My goal is for a small group of people (no more than 40) to be able to collaborate within a local area network. I need something that is self hosted, so unfortunately outside solutions like Skype and hosted Lync would not work. I'm looking for something that would allow both one on one, and group communication, so and IRC server would not work. I'm hopefully looking for something that does not require multiple servers, or is too complex to set up. As a student, I have a license of Lync 2013, but setting that up on a single server without active directory is practically impossible. Would Lync 2010 be easier to do on a single server? Are there any other good solutions? Thanks

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  • DNS server redirect users on first visit

    - by Sihan Zheng
    I am looking for a DNS level solution, that redirects a user to a specific IP on the first visit, than directs them to the correct IP on subsequent visits. So the idea is, for example, if a user visits "malicioussite.com", the first time they try to resolve that DNS name, it resolves to the IP of an internal web server, showing them a warning. On subsequent resolves, the users would get the actual IP, so they can visit the site. How can this be achieved? I am really flexible on what I can use, as long as its on the DNS level.

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  • shutdown -i all computers in active directory domain

    - by Sihan Zheng
    I'm not sure if this is possible, but this is my goal: At the end of the day, I want to be able to turn off all the computers in the domain from a client. My account has sufficient privileges to shutdown any single computer remotely using shutdown -I, and I can RDP into any computer in the domain. However, is there an automated technique that does this? the computers in the domain are predictably named (computer1, computer2, etc), but than manipulating a list of 2000 computers in shutdown -I is pretty clumsy. Is there a way to shutdown every single computer in the domain from a single client? The domain server is windows 2003, and the clients all run windows xp thanks

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  • In mercurial, is there a way to disable ALL configurations (system, user, repo)?

    - by Geoffrey Zheng
    On any non-trivial hg installation, the hgrc's tend to contain significant stuff. Is there a way to completely ignore/bypass ALL configurations, from system, user, to repo-level? The use case is to use some hg core functionalities in some automation scripts. Currently, if anything is misconfigured (and I mess with my ~/.hgrc a lot), the scripts will abort for something it doesn't use at all. It'd be perfect is I can just hg <whatever> --config:none.

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  • ArchBeat Facebook Friday: Top 10 Posts - August 8-14, 2014

    - by Bob Rhubart-Oracle
    5,307 people pay attention to the OTN ArchBeat Facebook Page. Here are the Top 10 posts from that page for the last seven days, August 8-14, 2014. Podcast: ODTUG Kscope 2014: Anatomy of a User Conference - Part 3 There is more to a great user conference than a shared interest in Oracle products. In the final segment of this 3-part OTN ArchBeat Podcast panelists Danny Bryant , Chet "ORACLENERD" Justice, Cameron Lackpour, Debra Lilley, and Mike Riley discuss the nature and importance of community Oracle SOA Suite 12c: The LDAP Adapter quick and easy | Maarten Smeets Maarten Smeets' how-to post describes the installation and configuration of an LDAP server and browser (ApacheDS and Apache Directory Studio). Process level Exception Handling in BPM12c | Abhishek Mittal When an exception occurs while running a process flow you have two choices: 1) retry running the flow object that caused that process flow or 2) move the process instance to the next flow object in the main process flow. Abhishek Mittal shows you how to do both. Building a Responsive WebCenter Portal Application | JayJay Zheng Oracle ACE JayJay Zheng's article addresses the essentials of responsive web design, shows you how to design and develop a responsive WebCenter Portal application, and reviews key development considerations. Cloud Control authorization with Active Directory | Jeroen Gouma Jeroen Gouma takes you step-by-step through the user authortization process in Oracle Enterprise Manager Cloud Control 12c. Video: CIOs Guide to Oracle Products and Solutions | Jessica Keyes The CIO's Guide to Oracle Products and Solutions author Jessica Keyes talks about why input from users and developers is essential to CIOs who want to avoid being escorted out of the building by security guards. Read A CIO's Guide to Oracle Cloud Computing, a sample chapter from the book. Twitter Tuesday - Top 10 @ArchBeat Tweets - August 5-11, 2014 @OTNArchBeat followers from across the galaxy have spoken! Here are the Top 10 tweets for the past seven days. Topics include: Hyperion, OBIEE, ODI, Oracle MAF, and SOA Suite. Recap: Fusion Middleware Summer Camps - Lisbon 2014 | Simon Haslam Oracle ACE Director Simon Haslam's recap of his experience at the Oracle Fusion Middleware Summer Camp in Lisbon, Portugal will make you wish you had been there. WebLogic Data Source Connection Labeling | Steve Felts The connection labeling feature was added in WLS release 10.3.6, and enhanced in release WLS 12.1.3. This post by Steve Felts describes two new connection properties that can be configured on the data source descriptor. Why Mobile Apps <3 REST/JSON | Martin Jarvis Martin Jarvis explores the preference for REST and JSON over SOAP and XML for mobile web services.

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  • Archbeat Link-O-Rama Top 10 Facebook Faves for October 20-26, 2013

    - by OTN ArchBeat
    Here's this week's list of the Top 10 items shared on the OTN ArchBeat Facebook Page from October 27 - November 2, 2013. Visualizing and Process (Twitter) Events in Real Time with Oracle Coherence | Noah Arliss This OTN Virtual Developer Day session explores in detail how to create a dynamic HTML5 Web application that interacts with Oracle Coherence as it’s processing events in real time, using the Avatar project and Oracle Coherence’s Live Events feature. Part of OTN Virtual Developer Day: Harnessing the Power of Oracle WebLogic and Oracle Coherence, November 5, 2013. 9am to 1pm PT / 12pm to 4pm ET / 1pm to 5pm BRT. Register now! HTML5 Application Development with Oracle WebLogic Server | Doug Clarke This free OTN Virtual Developer Day session covers the support for WebSockets, RESTful data services, and JSON infrastructure available in Oracle WebLogic Server. Part of OTN Virtual Developer Day: Harnessing the Power of Oracle WebLogic and Oracle Coherence, November 5, 2013. 9am to 1pm PT / 12pm to 4pm ET / 1pm to 5pm BRT. Register now! Video: ADF BC and REST services | Frederic Desbiens Spend a few minutes with Oracle ADF principal product manager Frederic Desbiens and learn how to publish ADF Business Components as RESTful web services. One Client Two Clusters | David Felcey "Sometimes its desirable to have a client connect to multiple clusters, either because the data is dispersed or for instance the clusters are in different locations for high availability," says David Felcey. David shows you how in this post, which includes a simple example. Exceptions Handling and Notifications in ODI | Christophe Dupupet Oracle Fusion Middleware A-Team director Christophe Dupupet reviews the techniques that are available in Oracle Data Integrator to guarantee that the appropriate individuals are notified in the event that ODI processes are impacted by network outages or other mishaps. Securing WebSocket applications on Glassfish | Pavel Bucek WebSocket is a key capability standardized into Java EE 7. Many developers wonder how WebSockets can be secured. One very nice characteristic for WebSocket is that it in fact completely piggybacks on HTTP. In this post Pavel Bucek demonstrates how to secure WebSocket endpoints in GlassFish using TLS/SSL. Oracle Coherence, Split-Brain and Recovery Protocols In Detail | Ricardo Ferreira Ricardo Ferreira's article "provides a high level conceptual overview of Split-Brain scenarios in distributed systems," focusing on a "specific example of cluster communication failure and recovery in Oracle Coherence." Non-programmatic Authentication Using Login Form in JSF (For WebCenter & ADF) | JayJay Zheng Oracle ACE JayJay Zheng shares an approach that "avoids the programmatic authentication and works great for having a custom login page developed in WebCenter Portal integrated with OAM authentication." The latest article in the Industrial SOA series looks at mobile computing and how companies are developing SOA to go. http://pub.vitrue.com/PUxT Tech Article: SOA in Real Life: Mobile Solutions The ACE Director Thing | Dr. Frank Munz Frank Munz finally gets around to blogging about achieving Oracle ACE Director status and shares some interesting insight into what will change—and what won't—thanks to that new status. A good, short read for those interested in learning more about the Oracle ACE program. Thought for the Day "Even if you're on the right track, you'll get run over if you just sit there." — Will Rogers, American humorist (November 4, 1879 – August 15, 1935) Source: brainyquote.com

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  • Apache OpenOffice dans le Cloud : premier prototype en HTML5, avant une déclinaison sur Smartphones ?

    OpenOffice dans le Cloud : Apache fait une démo d'un premier prototype en HTML5 Avant une déclinaison sur Smartphones ? C'est la Fondation Apache qui le dit. OpenOffice a été la star de la deuxième journée de l'ApacheCon Europe. On ne pourra pas lui donner tort puisque deux de ses membres - Jian Hong Cheng et Fan Zheng ? ont fait la démonstration de la très attendue première version "Cloud" de la suite bureautique open-source. [IMG]http://ftp-developpez.com/gordon-fowler/OpenOffice%20Cloud/OpenOffice%20Cloud%201small.jpg[/IMG...

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  • Top 10 Architect Community Articles for May 2014

    - by OTN ArchBeat
    One of the things I get to do as an OTN community manager is work with members of the architect community who want to spend extra time pounding the keyboard and risking carpal tunnel syndrome to publish articles on OTN. These articles typically cover—but are not limited to—middleware technologies (the other OTN community managers cover other technologies and product areas). Naturally, we track the popularity of these articles and use that information to help guide editorial decisions about the many article submissions we get. The list below represents the Top 10 most popular architect community articles for May 2014. (This list reflects only articles published between June 1, 2013 and May 31, 2014.) Cookbook: Installing and Configuring Oracle BI Applications 11.1.1.7.1 [August 2013] by Mark Rittman and Kevin McGinley Enterprise Service Bus [July 2013] by Jürgen Kress, Berthold Maier, Hajo Normann, Danilo Schmeidel, Guido Schmutz, Bernd Trops, Clemens Utschig-Utschig, Torsten Winterberg Back Up a Thousand Databases Using Enterprise Manager Cloud Control 12c [January 2014] by Porus Homi Havewala Set Up and Manage Oracle Data Guard using Oracle Enterprise Manager Cloud Control 12c [August 2013] by Porus Homi Havewala SOA and Cloud Computing [April 2014] by Jürgen Kress, Berthold Maier, Hajo Normann, Danilo Schmeidel, Guido Schmutz, Bernd Trops, Clemens Utschig-Utschig, Torsten Winterberg Building a Responsive WebCenter Portal Application [April 2014] by JayJay Zheng Using WebLogic 12c with Netbeans IDE by Markus Eisele Making the Move from Oracle Warehouse Builder to Oracle Data Integrator 12c by Stewart Bryson A Real-World Guide to Invoking OSB and EDN using C++ and Web Services [January 2014] by Sebastian Lik-Keung Ma Why Would Anyone Want to be an Architect? [May 2014] by Bob Rhubart If this list leaves you feeling inspired to write a technical article for OTN, or if you have questions about the process, drop me line in the comments section, below. I'll get back to you ASAP.

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  • JTable Design Guide in Swing Application

    - by zwang
    I have a really hard design problem in my swing application. Generally Speaking, I have a JTable and a JLabel to display. The label is right below the JTable. When the height of these two components doesn't exceed a threshold, then the jtable and label displays as normal. Then height of these two components will increase as the number of records filled in the table increases. When the height of these two components exceeds a threshold, I want there is a scrollbar in the JTable and the height of these two components will be the threshold. Is this design Possible? I have draft to illustate my UI design requirement. But I don't know how to post it in this forum. And any reply are appreciate. Best Regards, Zheng.

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  • CodePlex Daily Summary for Friday, May 14, 2010

    CodePlex Daily Summary for Friday, May 14, 2010New ProjectsCampfire#: Campfire# is a campfire client written in .NET 4.0 using WPF, which uses the Campfire API.CHESS: Systematic Concurrency Testing: CHESS is a tool for systematic and disciplined concurrency testing. Given a concurrent test, CHESS systematically enumerates the possible thread sc...cmpp: cmppcycloid: Arcanoid gameDotNetNuke® C#: The DotNetNuke® project is developed and maintained on a Visual Basic codebase, however a C# version has always been a popular request. This is a ...EasyBuildingCMS.NET: EasyBuildingCMS is an easy use content management system.fluidCMS: Provide for flexible management of web content that is not tightly integrated with the layout and rendering of sites that consume the content.Golem: An automation tool oriented to localization engineering environmentHB Batch Encoder Mk 2: HandBrake Batch Encoder Mk II This Program was adapted from an original project downloaded from codeplex by the name of "Handbrake Batch Encoder"...Integrating Social Media Networks: This is part of my pos graduation project.Ketonic: The Ketonic project aims to improve development of websites based on the Kentico CMS. LinkSharp: LinkSharp is a short-URL provider that can be used to generate short static non changing URL's. The web interface allows you to easily add / edit /...PUC NET (C++ Network Library - PUC Minas): This is an Academic Library for an Easy Development of Applications and Games based on Network Communication.Regular Expression Tester: Small utility for testing regular expressionsSharePoint User Management WebPart: SharePoint User Management WebPartSharpBox: SharpBox makes it easier for .NET developers to interact with existing cloud storage service, e.g. DropBox or Amazon S3Snipivit: Snipivit is a snippet manager service and VS2010 plugin that allows small development teams to store all their code snippets on a central database,...Software Factories Applied: Software Factories Applied is a project collecting the companion bits for the eponymous book to be published by Wiley & Sons in 2011. The authors ...The Ping Master: A service that periodically pings network addresses and allows the running of command line type utilities in response to success or failure.Title Safe Region Checker: A simple utility for XNA developers to check screenshots from games intended for release on the LIVE Marketplace for "title safe" region compliance...Trial project: sky is blueUyghur Named Date: Generate Uyghur named date string. ئۇيغۇرچە ئاي ناملىق چىسلا ھاسىل قىلىشWildcard Search Web Part for SharePoint 2010: The Wildcard Search web part for MOSS 2007 was wildly successful. Although, SharePoint 2010 has built-in wildcard searching functionality, the out...在线Office控件 Online Offical Control: 在线Office控件软件作品发布平台: SoftwarePublishPlatform 软件作品发布平台New ReleasesDemina: Demina Binaries version 0.1: Demina binaries are now available. This release (version 0.1) is an alpha version. Please report any bugs for extermination.EasyTFS: EasyTfs 1.0 Beta 2: Added cache refreshing when contents are updated rather than just every 10 minutes. Added window title based on currently-open case. Added attachme...Extending C# editor - Outlining, classification: Initial release: Initial releaseHB Batch Encoder Mk 2: HB Batch Encoder Mk2 v1.01: Binary release files.HB Batch Encoder Mk 2: Source Code: Source CodeHobbyBrew Mobile: Beta 2: Corretti numerosi bug, data un implementazione "approssimativa" del riscaldamento per Infusione. Aggiornamento consigliato!HouseFly controls: HouseFly controls beta 1.0.2.0: HouseFly controls relase 1.0.2.0 betaHtml Reader: Beta 2: I fixed a bug in HtmlElementCollection, Which exposed an integer enumerator, instead of enumerating through HtmlElements. I added a WPF Window tha...Html to OpenXml: HtmlToOpenXml 1.2: Fix some reported bug. See change set for description. The dll library to include in your project. The dll is signed for GAC support. Compiled wi...Infection Protection: Infection Protection 0.1: This is the final version of Infection Protection that was entered into the 2010 OGPC game competition.Jobping Url Shortener: Deploy Code 0.5.1: Deployment code for Version 0.5 This version includes our Jobping style.Jobping Url Shortener: Source Code 0.5.1: Source code for the 0.5 release. This release includes our Jobping style skin.Kooboo HTML form: Kooboo HTML form module 2.1.0.1: HTML form module contributed by member aledelgo. Add SMTP user and password authentication.KooBoo Image Galery: Beta 2: This new version corrects some issues pointed by Guoqi Zheng Some schema and folders were renamed, so it's better to uninstall the module and remo...MFCMAPI: May 2010 Release: If you just want to run the tool, get the executable. If you want to debug it, get the symbol file and the source. Build: 6.0.0.1020 The 64 bit bu...MVC Turbine: Release 2.1 for MVC2: This RTM contains the same features as v2.0 RTM plus these features: Instance Registration to IServiceLocator You can now add an instance of a typ...NazTek.Extension.Clr4: NazTek.Extension.Clr4 Binary: Binary releaseNazTek.Extension.Clr4: NazTek.Extension.Clr4 Source: Cab with source codeNSIS Autorun: NSIS Autorun 0.1.8: This release includes source code, executable binaries and example materials.Ottawa IT Day: 2010 Source Code and Presentations: During the Ottawa IT Day 2010, some of the presenters shared their code (and some presentations). This release is the culmination of all those effo...PHPWord: PHPWord 0.6.1 Beta: Changelog: Fixed Error when adding a JPEG image and opening in office 2007 Issue #1 Fixed Already defined constant PHPWORD_BASE_PATH Issue #2 F...Rapid Dictionary: Rapid Dictionary Alpha 2.0: Release Notes * Try auto updatable version: http://install.rapiddict.com/index.html Rapid Dictionary Alpha 2.0 includes such functionality: ...Shake - C# Make: Shake v0.1.18: Core changes. Process wrapper class, console logger, etc.SharpBox: SharpBox-Trunk: This is the SharpBox build from the trunk source branch!SharpBox: SharpBox-Trunk-Initial-Source: The initial source code, will be updated from time to timeSpackle.NET: 4.0.0.0 Release: This new drop contains the following A CreateBigInteger() method on SecureRandom to create random BigInteger values. An extension method to prop...StreamInsight example queries, input adapters and output adapters: StreamInsight Examples for V1.0 RTM: Zipped source code.The Ping Master: v0.1.0.0: Early release of The Ping Master for test purposes. Configuration tool is unfinished and does not include an installer.Title Safe Region Checker: Title Safe Region Checker v1.0.0.1: Release 1.0 of Title Safe Region Checker. No known bugs or problems. File is a zipped directory containing the necessary installation files.TortoiseHg: TortoiseHg 1.0.3: This is a bug fix release, we recommend all users upgrade to 1.0.3Usa*Usa Libraly: Smart.Windows.Navigation 0.4: Smart.Windows.Navigation simple navigation library ver 0.4.0. Include Windows Forms & Compact Framework samples. Information - Smart.Windows.Mvc ...VCC: Latest build, v2.1.30513.0: Automatic drop of latest buildWabbitStudio Z80 Software Tools: Wabbitcode: Wabbitcode is an Z80 Assembly IDE for Windows, OS X, and Linux. Built to take full advantage of the features of SPASM and Wabbitemu, Wabbitcode has...white: Release 0.20: Source Code: https://white-project.googlecode.com/svn/tags/0.20 Add few more keyboard keys like windows button and F13-F24. Fixed bugs for keyboar...Wildcard Search Web Part for SharePoint 2010: Version 1.0 Release 1: This is the initial release of the Wildcard Search Web Part for SharePoint 2010. All queries will be issued as wildcards unless disabled with the ...Windows Azure Command-line Tools for PHP Developers: Windows Azure Command-line Tools May 2010 Update: May 2010 Update – May 13, 2010 We are pleased to announced the May 2010 update of Windows Azure Command-Line Tools. In addition to bug fixes and i...WinXmlCook: WinXmlCook 2.1: Version 2.1 released!Xrns2XMod: Xrns2XMod 1.1: some source code optimization在线Office控件 Online Offical Control: SPOffice2.0Release: 该版本在MS Office2003/2007,WPS2009,WPS2010下测试通过Most Popular ProjectsRawrWBFS ManagerAJAX Control ToolkitMicrosoft SQL Server Product Samples: DatabaseSilverlight ToolkitWindows Presentation Foundation (WPF)patterns & practices – Enterprise LibraryMicrosoft SQL Server Community & SamplesPHPExcelASP.NETMost Active Projectspatterns & practices – Enterprise LibraryMirror Testing SystemRawrBlogEngine.NETPHPExcelMicrosoft Biology FoundationwhiteWindows Azure Command-line Tools for PHP DevelopersStyleCopShake - C# Make

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  • CLSF & CLK 2013 Trip Report by Jeff Liu

    - by jamesmorris
    This is a contributed post from Jeff Liu, lead XFS developer for the Oracle mainline Linux kernel team. Recently, I attended both the China Linux Storage and Filesystem workshop (CLSF), and the China Linux Kernel conference (CLK), which were held in Shanghai. Here are the highlights for both events. CLSF - 17th October XFS update (led by Jeff Liu) XFS keeps rapid progress with a lot of changes, especially focused on the infrastructure/performance improvements as well as  new feature development.  This can be reflected with a sample statistics among XFS/Ext4+JBD2/Btrfs via: # git diff --stat --minimal -C -M v3.7..v3.12-rc4 -- fs/xfs|fs/ext4+fs/jbd2|fs/btrfs XFS: 141 files changed, 27598 insertions(+), 19113 deletions(-) Ext4+JBD2: 39 files changed, 10487 insertions(+), 5454 deletions(-) Btrfs: 70 files changed, 19875 insertions(+), 8130 deletions(-) What made up those changes in XFS? Self-describing metadata(CRC32c). This is a new feature and it contributed about 70% code changes, it can be enabled via `mkfs.xfs -m crc=1 /dev/xxx` for v5 superblock. Transaction log space reservation improvements. With this change, we can calculate the log space reservation at mount time rather than runtime to reduce the the CPU overhead. User namespace support. So both XFS and USERNS can be enabled on kernel configuration begin from Linux 3.10. Thanks Dwight Engen's efforts for this thing. Split project/group quota inodes. Originally, project quota can not be enabled with group quota at the same time because they were share the same quota file inode, now it works but only for v5 super block. i.e, CRC enabled. CONFIG_XFS_WARN, an new lightweight runtime debugger which can be deployed in production environment. Readahead log object recovery, this change can speed up the log replay progress significantly. Speculative preallocation inode tracking, clearing and throttling. The main purpose is to deal with inodes with post-EOF space due to speculative preallocation, support improved quota management to free up a significant amount of unwritten space when at or near EDQUOT. It support backgroup scanning which occurs on a longish interval(5 mins by default, tunable), and on-demand scanning/trimming via ioctl(2). Bitter arguments ensued from this session, especially for the comparison between Ext4 and Btrfs in different areas, I have to spent a whole morning of the 1st day answering those questions. We basically agreed on XFS is the best choice in Linux nowadays because: Stable, XFS has a good record in stability in the past 10 years. Fengguang Wu who lead the 0-day kernel test project also said that he has observed less error than other filesystems in the past 1+ years, I own it to the XFS upstream code reviewer, they always performing serious code review as well as testing. Good performance for large/small files, XFS does not works very well for small files has already been an old story for years. Best choice (maybe) for distributed PB filesystems. e.g, Ceph recommends delopy OSD daemon on XFS because Ext4 has limited xattr size. Best choice for large storage (>16TB). Ext4 does not support a single file more than around 15.95TB. Scalability, any objection to XFS is best in this point? :) XFS is better to deal with transaction concurrency than Ext4, why? The maximum size of the log in XFS is 2038MB compare to 128MB in Ext4. Misc. Ext4 is widely used and it has been proved fast/stable in various loads and scenarios, XFS just need more customers, and Btrfs is still on the road to be a manhood. Ceph Introduction (Led by Li Wang) This a hot topic.  Li gave us a nice introduction about the design as well as their current works. Actually, Ceph client has been included in Linux kernel since 2.6.34 and supported by Openstack since Folsom but it seems that it has not yet been widely deployment in production environment. Their major work is focus on the inline data support to separate the metadata and data storage, reduce the file access time, i.e, a file access need communication twice, fetch the metadata from MDS and then get data from OSD, and also, the small file access is limited by the network latency. The solution is, for the small files they would like to store the data at metadata so that when accessing a small file, the metadata server can push both metadata and data to the client at the same time. In this way, they can reduce the overhead of calculating the data offset and save the communication to OSD. For this feature, they have only run some small scale testing but really saw noticeable improvements. Test environment: Intel 2 CPU 12 Core, 64GB RAM, Ubuntu 12.04, Ceph 0.56.6 with 200GB SATA disk, 15 OSD, 1 MDS, 1 MON. The sequence read performance for 1K size files improved about 50%. I have asked Li and Zheng Yan (the core developer of Ceph, who also worked on Btrfs) whether Ceph is really stable and can be deployed at production environment for large scale PB level storage, but they can not give a positive answer, looks Ceph even does not spread over Dreamhost (subject to confirmation). From Li, they only deployed Ceph for a small scale storage(32 nodes) although they'd like to try 6000 nodes in the future. Improve Linux swap for Flash storage (led by Shaohua Li) Because of high density, low power and low price, flash storage (SSD) is a good candidate to partially replace DRAM. A quick answer for this is using SSD as swap. But Linux swap is designed for slow hard disk storage, so there are a lot of challenges to efficiently use SSD for swap. SWAPOUT swap_map scan swap_map is the in-memory data structure to track swap disk usage, but it is a slow linear scan. It will become a bottleneck while finding many adjacent pages in the use of SSD. Shaohua Li have changed it to a cluster(128K) list, resulting in O(1) algorithm. However, this apporoach needs restrictive cluster alignment and only enabled for SSD. IO pattern In most cases, the swap io is in interleaved pattern because of mutiple reclaimers or a free cluster is shared by all reclaimers. Even though block layer can merge interleaved IO to some extent, but we cannot count on it completely. Hence the per-cpu cluster is added base on the previous change, it can help reclaimer do sequential IO and the block layer will be easier to merge IO. TLB flush: If we're reclaiming one active page, we should first move the page from active lru list to inactive lru list, and then reclaim the page from inactive lru to swap it out. During the process, we need to clear PTE twice: first is 'A'(ACCESS) bit, second is 'P'(PRESENT) bit. Processors need to send lots of ipi which make the TLB flush really expensive. Some works have been done to improve this, including rework smp_call_functiom_many() or remove the first TLB flush in x86, but there still have some arguments here and only parts of works have been pushed to mainline. SWAPIN: Page fault does iodepth=1 sync io, but it's a little waste if only issue a page size's IO. The obvious solution is doing swap readahead. But the current in-kernel swap readahead is arbitary(always 8 pages), and it always doesn't perform well for both random and sequential access workload. Shaohua introduced a new flag for madvise(MADV_WILLNEED) to do swap prefetch, so the changes happen in userspace API and leave the in-kernel readahead unchanged(but I think some improvement can also be done here). SWAP discard As we know, discard is important for SSD write throughout, but the current swap discard implementation is synchronous. He changed it to async discard which allow discard and write run in the same time. Meanwhile, the unit of discard is also optimized to cluster. Misc: lock contention For many concurrent swapout and swapin , the lock contention such as anon_vma or swap_lock is high, so he changed the swap_lock to a per-swap lock. But there still have some lock contention in very high speed SSD because of swapcache address_space lock. Zproject (led by Bob Liu) Bob gave us a very nice introduction about the current memory compression status. Now there are 3 projects(zswap/zram/zcache) which all aim at smooth swap IO storm and promote performance, but they all have their own pros and cons. ZSWAP It is implemented based on frontswap API and it uses a dynamic allocater named Zbud to allocate free pages. Zbud means pairs of zpages are "buddied" and it can only store at most two compressed pages in one page frame, so the max compress ratio is 50%. Each page frame is lru-linked and can do shink in memory pressure. If the compressed memory pool reach its limitation, shink or reclaim happens. It decompress the page frame into two new allocated pages and then write them to real swap device, but it can fail when allocating the two pages. ZRAM Acts as a compressed ramdisk and used as swap device, and it use zsmalloc as its allocator which has high density but may have fragmentation issues. Besides, page reclaim is hard since it will need more pages to uncompress and free just one page. ZRAM is preferred by embedded system which may not have any real swap device. Now both ZRAM and ZSWAP are in driver/staging tree, and in the mm community there are some disscussions of merging ZRAM into ZSWAP or viceversa, but no agreement yet. ZCACHE Handles file page compression but it is removed out of staging recently. From industry (led by Tang Jie, LSI) An LSI engineer introduced several new produces to us. The first is raid5/6 cards that it use full stripe writes to improve performance. The 2nd one he introduced is SandForce flash controller, who can understand data file types (data entropy) to reduce write amplification (WA) for nearly all writes. It's called DuraWrite and typical WA is 0.5. What's more, if enable its Dynamic Logical Capacity function module, the controller can do data compression which is transparent to upper layer. LSI testing shows that with this virtual capacity enables 1x TB drive can support up to 2x TB capacity, but the application must monitor free flash space to maintain optimal performance and to guard against free flash space exhaustion. He said the most useful application is for datebase. Another thing I think it's worth to mention is that a NV-DRAM memory in NMR/Raptor which is directly exposed to host system. Applications can directly access the NV-DRAM via a memory address - using standard system call mmap(). He said that it is very useful for database logging now. This kind of NVM produces are beginning to appear in recent years, and it is said that Samsung is building a research center in China for related produces. IMHO, NVM will bring an effect to current os layer especially on file system, e.g. its journaling may need to redesign to fully utilize these nonvolatile memory. OCFS2 (led by Canquan Shen) Without a doubt, HuaWei is the biggest contributor to OCFS2 in the past two years. They have posted 46 upstream patches and 39 patches have been merged. Their current project is based on 32/64 nodes cluster, but they also tried 128 nodes at the experimental stage. The major work they are working is to support ATS (atomic test and set), it can be works with DLM at the same time. Looks this idea is inspired by the vmware VMFS locking, i.e, http://blogs.vmware.com/vsphere/2012/05/vmfs-locking-uncovered.html CLK - 18th October 2013 Improving Linux Development with Better Tools (Andi Kleen) This talk focused on how to find/solve bugs along with the Linux complexity growing. Generally, we can do this with the following kind of tools: Static code checkers tools. e.g, sparse, smatch, coccinelle, clang checker, checkpatch, gcc -W/LTO, stanse. This can help check a lot of things, simple mistakes, complex problems, but the challenges are: some are very slow, false positives, may need a concentrated effort to get false positives down. Especially, no static checker I found can follow indirect calls (“OO in C”, common in kernel): struct foo_ops { int (*do_foo)(struct foo *obj); } foo->do_foo(foo); Dynamic runtime checkers, e.g, thread checkers, kmemcheck, lockdep. Ideally all kernel code would come with a test suite, then someone could run all the dynamic checkers. Fuzzers/test suites. e.g, Trinity is a great tool, it finds many bugs, but needs manual model for each syscall. Modern fuzzers around using automatic feedback, but notfor kernel yet: http://taviso.decsystem.org/making_software_dumber.pdf Debuggers/Tracers to understand code, e.g, ftrace, can dump on events/oops/custom triggers, but still too much overhead in many cases to run always during debug. Tools to read/understand source, e.g, grep/cscope work great for many cases, but do not understand indirect pointers (OO in C model used in kernel), give us all “do_foo” instances: struct foo_ops { int (*do_foo)(struct foo *obj); } = { .do_foo = my_foo }; foo>do_foo(foo); That would be great to have a cscope like tool that understands this based on types/initializers XFS: The High Performance Enterprise File System (Jeff Liu) [slides] I gave a talk for introducing the disk layout, unique features, as well as the recent changes.   The slides include some charts to reflect the performances between XFS/Btrfs/Ext4 for small files. About a dozen users raised their hands when I asking who has experienced with XFS. I remembered that when I asked the same question in LinuxCon/Japan, only 3 people raised their hands, but they are Chris Mason, Ric Wheeler, and another attendee. The attendee questions were mainly focused on stability, and comparison with other file systems. Linux Containers (Feng Gao) The speaker introduced us that the purpose for those kind of namespaces, include mount/UTS/IPC/Network/Pid/User, as well as the system API/ABI. For the userspace tools, He mainly focus on the Libvirt LXC rather than us(LXC). Libvirt LXC is another userspace container management tool, implemented as one type of libvirt driver, it can manage containers, create namespace, create private filesystem layout for container, Create devices for container and setup resources controller via cgroup. In this talk, Feng also mentioned another two possible new namespaces in the future, the 1st is the audit, but not sure if it should be assigned to user namespace or not. Another is about syslog, but the question is do we really need it? In-memory Compression (Bob Liu) Same as CLSF, a nice introduction that I have already mentioned above. Misc There were some other talks related to ACPI based memory hotplug, smart wake-affinity in scheduler etc., but my head is not big enough to record all those things. -- Jeff Liu

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  • Testing Entity Framework applications, pt. 3: NDbUnit

    - by Thomas Weller
    This is the third of a three part series that deals with the issue of faking test data in the context of a legacy app that was built with Microsoft's Entity Framework (EF) on top of an MS SQL Server database – a scenario that can be found very often. Please read the first part for a description of the sample application, a discussion of some general aspects of unit testing in a database context, and of some more specific aspects of the here discussed EF/MSSQL combination. Lately, I wondered how you would ‘mock’ the data layer of a legacy application, when this data layer is made up of an MS Entity Framework (EF) model in combination with a MS SQL Server database. Originally, this question came up in the context of how you could enable higher-level integration tests (automated UI tests, to be exact) for a legacy application that uses this EF/MSSQL combo as its data store mechanism – a not so uncommon scenario. The question sparked my interest, and I decided to dive into it somewhat deeper. What I've found out is, in short, that it's not very easy and straightforward to do it – but it can be done. The two strategies that are best suited to fit the bill involve using either the (commercial) Typemock Isolator tool or the (free) NDbUnit framework. The use of Typemock was discussed in the previous post, this post now will present the NDbUnit approach... NDbUnit is an Apache 2.0-licensed open-source project, and like so many other Nxxx tools and frameworks, it is basically a C#/.NET port of the corresponding Java version (DbUnit namely). In short, it helps you in flexibly managing the state of a database in that it lets you easily perform basic operations (like e.g. Insert, Delete, Refresh, DeleteAll)  against your database and, most notably, lets you feed it with data from external xml files. Let's have a look at how things can be done with the help of this framework. Preparing the test data Compared to Typemock, using NDbUnit implies a totally different approach to meet our testing needs.  So the here described testing scenario requires an instance of an SQL Server database in operation, and it also means that the Entity Framework model that sits on top of this database is completely unaffected. First things first: For its interactions with the database, NDbUnit relies on a .NET Dataset xsd file. See Step 1 of their Quick Start Guide for a description of how to create one. With this prerequisite in place then, the test fixture's setup code could look something like this: [TestFixture, TestsOn(typeof(PersonRepository))] [Metadata("NDbUnit Quickstart URL",           "http://code.google.com/p/ndbunit/wiki/QuickStartGuide")] [Description("Uses the NDbUnit library to provide test data to a local database.")] public class PersonRepositoryFixture {     #region Constants     private const string XmlSchema = @"..\..\TestData\School.xsd";     #endregion // Constants     #region Fields     private SchoolEntities _schoolContext;     private PersonRepository _personRepository;     private INDbUnitTest _database;     #endregion // Fields     #region Setup/TearDown     [FixtureSetUp]     public void FixtureSetUp()     {         var connectionString = ConfigurationManager.ConnectionStrings["School_Test"].ConnectionString;         _database = new SqlDbUnitTest(connectionString);         _database.ReadXmlSchema(XmlSchema);         var entityConnectionStringBuilder = new EntityConnectionStringBuilder         {             Metadata = "res://*/School.csdl|res://*/School.ssdl|res://*/School.msl",             Provider = "System.Data.SqlClient",             ProviderConnectionString = connectionString         };         _schoolContext = new SchoolEntities(entityConnectionStringBuilder.ConnectionString);         _personRepository = new PersonRepository(this._schoolContext);     }     [FixtureTearDown]     public void FixtureTearDown()     {         _database.PerformDbOperation(DbOperationFlag.DeleteAll);         _schoolContext.Dispose();     }     ...  As you can see, there is slightly more fixture setup code involved if your tests are using NDbUnit to provide the test data: Because we're dealing with a physical database instance here, we first need to pick up the test-specific connection string from the test assemblies' App.config, then initialize an NDbUnit helper object with this connection along with the provided xsd file, and also set up the SchoolEntities and the PersonRepository instances accordingly. The _database field (an instance of the INdUnitTest interface) will be our single access point to the underlying database: We use it to perform all the required operations against the data store. To have a flexible mechanism to easily insert data into the database, we can write a helper method like this: private void InsertTestData(params string[] dataFileNames) {     _database.PerformDbOperation(DbOperationFlag.DeleteAll);     if (dataFileNames == null)     {         return;     }     try     {         foreach (string fileName in dataFileNames)         {             if (!File.Exists(fileName))             {                 throw new FileNotFoundException(Path.GetFullPath(fileName));             }             _database.ReadXml(fileName);             _database.PerformDbOperation(DbOperationFlag.InsertIdentity);         }     }     catch     {         _database.PerformDbOperation(DbOperationFlag.DeleteAll);         throw;     } } This lets us easily insert test data from xml files, in any number and in a  controlled order (which is important because we eventually must fulfill referential constraints, or we must account for some other stuff that imposes a specific ordering on data insertion). Again, as with Typemock, I won't go into API details here. - Unfortunately, there isn't too much documentation for NDbUnit anyway, other than the already mentioned Quick Start Guide (and the source code itself, of course) - a not so uncommon problem with smaller Open Source Projects. Last not least, we need to provide the required test data in xml form. A snippet for data from the People table might look like this, for example: <?xml version="1.0" encoding="utf-8" ?> <School xmlns="http://tempuri.org/School.xsd">   <Person>     <PersonID>1</PersonID>     <LastName>Abercrombie</LastName>     <FirstName>Kim</FirstName>     <HireDate>1995-03-11T00:00:00</HireDate>   </Person>   <Person>     <PersonID>2</PersonID>     <LastName>Barzdukas</LastName>     <FirstName>Gytis</FirstName>     <EnrollmentDate>2005-09-01T00:00:00</EnrollmentDate>   </Person>   <Person>     ... You can also have data from various tables in one single xml file, if that's appropriate for you (but beware of the already mentioned ordering issues). It's true that your test assembly may end up with dozens of such xml files, each containing quite a big amount of text data. But because the files are of very low complexity, and with the help of a little bit of Copy/Paste and Excel magic, this appears to be well manageable. Executing some basic tests Here are some of the possible tests that can be written with the above preparations in place: private const string People = @"..\..\TestData\School.People.xml"; ... [Test, MultipleAsserts, TestsOn("PersonRepository.GetNameList")] public void GetNameList_ListOrdering_ReturnsTheExpectedFullNames() {     InsertTestData(People);     List<string> names =         _personRepository.GetNameList(NameOrdering.List);     Assert.Count(34, names);     Assert.AreEqual("Abercrombie, Kim", names.First());     Assert.AreEqual("Zheng, Roger", names.Last()); } [Test, MultipleAsserts, TestsOn("PersonRepository.GetNameList")] [DependsOn("RemovePerson_CalledOnce_DecreasesCountByOne")] public void GetNameList_NormalOrdering_ReturnsTheExpectedFullNames() {     InsertTestData(People);     List<string> names =         _personRepository.GetNameList(NameOrdering.Normal);     Assert.Count(34, names);     Assert.AreEqual("Alexandra Walker", names.First());     Assert.AreEqual("Yan Li", names.Last()); } [Test, TestsOn("PersonRepository.AddPerson")] public void AddPerson_CalledOnce_IncreasesCountByOne() {     InsertTestData(People);     int count = _personRepository.Count;     _personRepository.AddPerson(new Person { FirstName = "Thomas", LastName = "Weller" });     Assert.AreEqual(count + 1, _personRepository.Count); } [Test, TestsOn("PersonRepository.RemovePerson")] public void RemovePerson_CalledOnce_DecreasesCountByOne() {     InsertTestData(People);     int count = _personRepository.Count;     _personRepository.RemovePerson(new Person { PersonID = 33 });     Assert.AreEqual(count - 1, _personRepository.Count); } Not much difference here compared to the corresponding Typemock versions, except that we had to do a bit more preparational work (and also it was harder to get the required knowledge). But this picture changes quite dramatically if we look at some more demanding test cases: Ok, and what if things are becoming somewhat more complex? Tests like the above ones represent the 'easy' scenarios. They may account for the biggest portion of real-world use cases of the application, and they are important to make sure that it is generally sound. But usually, all these nasty little bugs originate from the more complex parts of our code, or they occur when something goes wrong. So, for a testing strategy to be of real practical use, it is especially important to see how easy or difficult it is to mimick a scenario which represents a more complex or exceptional case. The following test, for example, deals with the case that there is some sort of invalid input from the caller: [Test, MultipleAsserts, TestsOn("PersonRepository.GetCourseMembers")] [Row(null, typeof(ArgumentNullException))] [Row("", typeof(ArgumentException))] [Row("NotExistingCourse", typeof(ArgumentException))] public void GetCourseMembers_WithGivenVariousInvalidValues_Throws(string courseTitle, Type expectedInnerExceptionType) {     var exception = Assert.Throws<RepositoryException>(() =>                                 _personRepository.GetCourseMembers(courseTitle));     Assert.IsInstanceOfType(expectedInnerExceptionType, exception.InnerException); } Apparently, this test doesn't need an 'Arrange' part at all (see here for the same test with the Typemock tool). It acts just like any other client code, and all the required business logic comes from the database itself. This doesn't always necessarily mean that there is less complexity, but only that the complexity happens in a different part of your test resources (in the xml files namely, where you sometimes have to spend a lot of effort for carefully preparing the required test data). Another example, which relies on an underlying 1-n relationship, might be this: [Test, MultipleAsserts, TestsOn("PersonRepository.GetCourseMembers")] public void GetCourseMembers_WhenGivenAnExistingCourse_ReturnsListOfStudents() {     InsertTestData(People, Course, Department, StudentGrade);     List<Person> persons = _personRepository.GetCourseMembers("Macroeconomics");     Assert.Count(4, persons);     Assert.ForAll(         persons,         @p => new[] { 10, 11, 12, 14 }.Contains(@p.PersonID),         "Person has none of the expected IDs."); } If you compare this test to its corresponding Typemock version, you immediately see that the test itself is much simpler, easier to read, and thus much more intention-revealing. The complexity here lies hidden behind the call to the InsertTestData() helper method and the content of the used xml files with the test data. And also note that you might have to provide additional data which are not even directly relevant to your test, but are required only to fulfill some integrity needs of the underlying database. Conclusion The first thing to notice when comparing the NDbUnit approach to its Typemock counterpart obviously deals with performance: Of course, NDbUnit is much slower than Typemock. Technically,  it doesn't even make sense to compare the two tools. But practically, it may well play a role and could or could not be an issue, depending on how much tests you have of this kind, how often you run them, and what role they play in your development cycle. Also, because the dataset from the required xsd file must fully match the database schema (even in parts that otherwise wouldn't be relevant to you), it can be quite cumbersome to be in a team where different people are working with the database in parallel. My personal experience is – as already said in the first part – that Typemock gives you a better development experience in a 'dynamic' scenario (when you're working in some kind of TDD-style, you're oftentimes executing the tests from your dev box, and your database schema changes frequently), whereas the NDbUnit approach is a good and solid solution in more 'static' development scenarios (when you need to execute the tests less frequently or only on a separate build server, and/or the underlying database schema can be kept relatively stable), for example some variations of higher-level integration or User-Acceptance tests. But in any case, opening Entity Framework based applications for testing requires a fair amount of resources, planning, and preparational work – it's definitely not the kind of stuff that you would call 'easy to test'. Hopefully, future versions of EF will take testing concerns into account. Otherwise, I don't see too much of a future for the framework in the long run, even though it's quite popular at the moment... The sample solution A sample solution (VS 2010) with the code from this article series is available via my Bitbucket account from here (Bitbucket is a hosting site for Mercurial repositories. The repositories may also be accessed with the Git and Subversion SCMs - consult the documentation for details. In addition, it is possible to download the solution simply as a zipped archive – via the 'get source' button on the very right.). The solution contains some more tests against the PersonRepository class, which are not shown here. Also, it contains database scripts to create and fill the School sample database. To compile and run, the solution expects the Gallio/MbUnit framework to be installed (which is free and can be downloaded from here), the NDbUnit framework (which is also free and can be downloaded from here), and the Typemock Isolator tool (a fully functional 30day-trial is available here). Moreover, you will need an instance of the Microsoft SQL Server DBMS, and you will have to adapt the connection strings in the test projects App.config files accordingly.

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