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  • Two way replication

    - by Nidzaaaa
    I have a little problem... I have this case: -2 server instances -2 Databases -1 Table (5 columns) From server 1 I created publication to replicate all columns of table I have in 1. DB From server 2 I created subscription to pull all columns from table which is in server 1 DB But now, I need to publicate one columns of same table from server 2 to server 1 and also it has to be in same DB... I tried with using logic and creating publication for server 2 and subscription on server 1 but there is error appearing "You have selected the Publisher as a Subscriber and entered a subscription database that is the same as the publishing database. Select another subscription database." I hope someone understood my problem and have an answer for me, thanks in advance... p.s. Ask for more info if you need ...

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  • Transient mysqlcheck errors about "size of datafile" (file too small)

    - by Adam Backstrom
    Running mysqlcheck on a live database is giving me transient errors like this one: mydatabase.mytable error : Size of datafile is: 500719688 Should be: 501000484 error : Corrupt When I run the command again or check the table one-off using mysql, it's listed as OK. Is this just a side effect of running checks on live tables? Is it possible that data is not flushed, hence the strange discrepancy? We moved several databases this morning by shutting down mysqld on the source and rsyncing files across to the new server, but these are all MyISAM tables so I don't believe the two things are related. (But I mention it just in case.)

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  • Mercurial on shared network drive?

    - by user1164199
    Right now I have my repo on my local drive. In order to back it up, I have to copy .hg to a window's network drive. At Is it a good idea to put Mercurial Repository in shared Network drive?, Lasse Karlsen said the repo shouldn't be on a shared folder on a network server because "mercurial cannot reliably hold locks in all situations". Would this still be an issue when the repository is only updated by a single user? If so, can someone explain to me why the corruption happens? A while back our IT had problem setting up a mercurial server. I am very fond of mercurial (it has a great interface and is very easy to work with), but if it's going to be such a pain in the neck to set up for multiple users, I am willing to look for something else. Does anyone have any suggestions (with reasons)? I am looking for a revision control program that has the following attributes: 2. Good interface (allow you to easily see revision and changes to the code over multiple revisions). 3. Work as a local repo or a network repo. 4. IT will feel comfortable installing on their network. Thanks, Stephen

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  • Move database from SQL 7 to 2005 / 2008

    - by etechpartner
    I have several pretty large databases located in a SQL Server 7 box. Whats the best way to get them into SQL Server 2008? As far as I know, there were changes to the underlying file structures so I am not sure that a simple detach/attach would work. When I tried attaching from 2008 it complained strongly. "Version no longer supported" etc etc. What options do I have? Are there any tools on the market that can connect to both 7 and 2008 and then move the schema and data?

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  • sqlserver.exe uses 100% CPU

    - by Markus
    I've created an application (asp.net) that once a day syncs an entire database through XML-files. The sync first creates an transaction and then clears the databases tables and then starts to parse and insert the new rows into the database. When all the parsing is complete it commits the transaction. This works fine on a SQL Server 2005 (on another machine), but on SQL Server 2005 Express, the process starts to use 100% CPU after a while, and as I log the inserts being made I can see that it just stops inserting. No exception, it just stops inserting. Anyone got any idea what this may be? I've previously run the syncronization on another sql 2005 express (also on another computer), and that worked. The server has only 2GB RAM, could this be the problem?

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  • Has Javascript developed beyond what it was originally designed to do?

    - by Elliot Bonneville
    I've been talking with a friend about the purpose of Javascript, when and how it should be used, etc. He quoted that: JavaScript was designed to add interactivity to HTML pages [...] JavaScript gives HTML designers a programming tool HTML authors are normally not programmers, but JavaScript is a scripting language with a very simple syntax! Almost anyone can put small "snippets" of code into their HTML pages JavaScript can react to events A JavaScript can be set to execute when something happens, like when a page has finished loading or when a user clicks on an HTML element JavaScript can read and write HTML elements A JavaScript can read and change the content of an HTML element JavaScript can be used to validate data A JavaScript can be used to validate form data before it is submitted to a server. This saves the server from extra processing JavaScript can be used to detect the visitor's browser - A JavaScript can be used to detect the visitor's browser, and - depending on the browser - load another page specifically designed for that browser. JavaScript can be used to create cookies - A JavaScript can be used to store and retrieve information on the visitor's computer. However, it seems like Javascript's getting used to do a lot more than these days. My friend also advocates against using Javascript's OOP functionality, claiming that "you shouldn't be processing data, merely validating." Is Javascript really limited to validating data and making flashy graphics on a web page? He goes on to claim "you shouldn't be attempting to access databases through javascript" and also says " in general you don't want to be doing your heavy lifting in javascript". I can't say I agree with his opinion, but I'd like to get some more input on this. So, my question: Has Javascript evolved from the definition above to something more powerful, has the way we use it changed, or am I just plain wrong? While I realize this is a subjective question, I can't find any more information on it, so a few links would be good, if nothing else. I'm not looking for a debate, just an answer.

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  • Add Your Gmail Account to Outlook 2010 Using IMAP

    - by Mysticgeek
    If you’re upgrading from Outlook 2003 to 2010, you might want to use IMAP with your Gmail account to synchronize mail across multiple machines. Using our guide, you will be able to start using it in no time. Enable IMAP in Gmail First log into your Gmail account and open the Settings panel. Click on the Forwarding and POP/IMAP tab and verify IMAP is enabled and save changes. Next open Outlook 2010, click on the File tab to access the Backstage view. Click on Account Settings and Add and remove accounts or change existing connection settings. In the Account Settings window click on the New button. Enter in your name, email address, and password twice then click Next. Outlook will configure the email server settings, the amount of time it takes will vary. Provided everything goes correctly, the configuration will be successful and you can begin using your account. Manually Configure IMAP Settings If the above instructions don’t work, then we’ll need to manually configure the settings. Again, go into Auto Account Setup and select Manually configure server settings or additional server types and click Next.   Select Internet E-mail – Connect to POP or IMAP server to send and receive e-mail messages. Now we need to manually enter in our settings similar to the following. Under the Server Information section verify the following. Account Type: IMAP Incoming mail server: imap.gmail.com Outgoing mail server (SMTP): smtp.gmail.com Note: If you have a Google Apps account make sure to put the full email address ([email protected]) in the Your Name and User Name fields. Note: If you live outside of the US you might need to use imap.googlemail.com and smtp.googlemail.com Next, we need to click on the More Settings button… In the Internet E-mail Settings screen that pops up, click on the Outgoing Server tab, and check the box next to My outgoing server (SMTP) requires authentication. Also select the radio button next to Use same settings as my incoming mail server. In the same window click on the Advanced tab and verify the following. Incoming server: 993 Incoming server encrypted connection: SSL Outgoing server encrypted connection TLS Outgoing server: 587 Note: You will need to change the Outgoing server encrypted connection first, otherwise it will default back to port 25. Also, if TLS doesn’t work, we were able to successfully use Auto. Click OK when finished. Now we want to test the settings, before continuing on…it’s just easier that way incase something was entered incorrectly. To make sure the settings are tested, check the box Test Account Settings by clicking the Next button. If you’ve entered everything in correctly, both tasks will be completed successfully and you can close out of the window. and begin using your account via Outlook 2010. You’ll get a final congratulations message you can close out of… And begin using your account via Outlook 2010. Conclusion Using IMAP allows you to synchronize email across multiple machines and devices. The IMAP feature in Gmail is free to use, and this should get you started using it with Outlook 2010. If you’re still using 2007 or just upgraded to it, check out our guide on how to use Gmail IMAP in Outlook 2007. Similar Articles Productive Geek Tips Add Your Gmail To Windows Live MailForce Outlook 2007 to Download Complete IMAP ItemsUse Gmail IMAP in Microsoft Outlook 2007Prevent Outlook with Gmail IMAP from Showing Duplicate Tasks in the To-Do BarSetting up Gmail IMAP Support for Windows Vista Mail 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 VMware Workstation 7 Acronis Online Backup DVDFab 6 Revo Uninstaller Pro Cool Looking Skins for Windows Media Player 12 Move the Mouse Pointer With Your Face Movement Using eViacam Boot Windows Faster With Boot Performance Diagnostics Create Ringtones For Your Android Phone With RingDroid Enhance Your Laptop’s Battery Life With These Tips Easily Search Food Recipes With Recipe Chimp

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  • What is the Oracle Utilities Application Framework?

    - by Anthony Shorten
    The Oracle Utilities Application Framework is a reusable, scalable and flexible java based framework which allows other products to be built, configured and implemented in a standard way. Note: Even though the Framework is built in java it can be integrated with COBOL based extensions for backward compatibility. When Oracle Utilities Customer Care & Billing was migrated from V1 to V2, it was decided that the technical aspects of that product be separated to allow for reuse and independence from technical issues. The idea was that all the technical aspects would be concentrated in this separate product (i.e. a framework) and allow all products using the framework to concentrate on delivering superior functionality. The product was named the Oracle Utilities Application Framework (oufw is the product code). The technical components are contained in the Oracle Utilities Application Framework which can be summarized as follows: Metadata - The Oracle Utilities Application Framework is responsible for defining and using the metadata to define the runtime behavior of the product. All the metadata definition and management is contained within the Oracle Utilities Application Framework. UI Management - The Oracle Utilities Application Framework is responsible for defining and rendering the pages and responsible for ensuring the pages are in the appropriate format for the locale. Integration - The Oracle Utilities Application Framework is responsible for providing the integration points to the architecture. Refer to the Oracle Utilities Application Framework Integration Overview for more details Tools - The Oracle Utilities Application Framework provides a common set of facilities and tools that can be used across all products. Technology - The Oracle Utilities Application Framework is responsible for all technology standards compliance, platform support and integration. There are a number of products from the Tax and Utilities Global Business Unit as well as from the Financial Services Global Business Unit that are built upon the Oracle Utilities Application Framework. These products require the Oracle Utilities Application Framework to be installed first and then the product itself installed onto the framework to complete the installation process. There are a number of key benefits that the Oracle Utilities Application Framework provides to these products: Common facilities - The Oracle Utilities Application Framework provides a standard set of technical facilities that mean that products can concentrate in the unique aspects of their markets rather than making technical decisions. Common methods of configuration - The Oracle Utilities Application Framework standardizes the technical configuration process for a product. Customers can effectively reuse the configuration process across products. Multi-lingual and Multi-platform - The Oracle Utilities Application Framework allows the products to be offered in more markets and across multiple platforms for maximized flexibility. Common methods of implementation - The Oracle Utilities Application Framework standardizes the technical aspects of a product implementation. Customers can effectively reuse the technical implementation process across products. Quicker adoption of new technologies - As new technologies and standards are identified as being important for the product line, they can be integrated centrally benefiting multiple products. Cross product reuse - As enhancements to the Oracle Utilities Application Framework are identified by a particular product, all products can potentially benefit from the enhancement. Note: Use of the Oracle Utilities Application Framework does not preclude the introduction of product specific technologies or facilities to satisfy market needs. The framework minimizes the need and assists in the quick integration of a new product specific piece of technology (if necessary). The Framework is not available as a product itself and is bundled with Tax and Utilities Global Business Unit prodicts. At the present time the following products are on the Framework: Oracle Utilities Customer Care And Billing (V2 and above) Oracle Enterprise Taxation Management (V2 and above) Oracle Utilities Business Intelligence (V2 and above) Oracle Utilities Mobile Workforice Management (V2 and above)

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  • Speaker at developer conferences and user group meetings

    Catching up on a couple of sessions I did in the past. This article gives an overview of some of my activities. Mainly at the annual German Visual FoxPro Developer Conference also known as SQL-Server & ASP.NET Conference in Frankfurt. The below listed entries are excerpts from the original Conference Coverage documents you'll find on UniversalThread. German Visual FoxPro Developer Conference 2002 (1 session - Vendor session about Active FoxPro Pages 3.0) German Visual FoxPro Developer Conference 2003 (2.5 sessions - Visual FoxPro running on Linux) German Visual FoxPro Developer Conference 2004 (4 sessions - 2x Active FoxPro Pages, VFP on Linux, and VFP using additional databases) German Visual FoxPro Developer Conference 2005 (4 sessions - RegEx, XML, XSLT, and using free (as in beer) development tools) German Visual FoxPro Developer Conference 2006 (3 sessions - .NET interop via COM, writing own CLR host in VFP, and Active FoxPro Pages) Furthermore, I did a couple of (hopefully) interesting sessions at various user group meetings in Speyer and Stuttgart. A more comprehensive list is available under Presentations (in German language). And last but not least, back in May 2005 Microsoft Germany invited me to host a WebCast for MSDN on how to use 'Visual FoxPro mit Visual Studio 2005'. Unfortunately, I was too unexperienced and too nervous (first time ever), we experienced technical issues with the microphone, and the obviously low quality of recording demanded to replace it by a whole series on Visual FoxPro 9.0. The webcast covered the same topics I already described in other articles here on my blog. Despite the desaster I'd like to thank Ralf Westphal for his kind words afterwards - I really felt bad. Eventually, you might ask yourself why it stopped by the end of 2006... Well, new chapter in my life: Mauritius!

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  • What is Linq?

    - by Aamir Hasan
    The way data can be retrieved in .NET. LINQ provides a uniform way to retrieve data from any object that implements the IEnumerable<T> interface. With LINQ, arrays, collections, relational data, and XML are all potential data sources. Why LINQ?With LINQ, you can use the same syntax to retrieve data from any data source:var query = from e in employeeswhere e.id == 1select e.nameThe middle level represents the three main parts of the LINQ project: LINQ to Objects is an API that provides methods that represent a set of standard query operators (SQOs) to retrieve data from any object whose class implements the IEnumerable<T> interface. These queries are performed against in-memory data.LINQ to ADO.NET augments SQOs to work against relational data. It is composed of three parts.LINQ to SQL (formerly DLinq) is use to query relational databases such as Microsoft SQL Server. LINQ to DataSet supports queries by using ADO.NET data sets and data tables. LINQ to Entities is a Microsoft ORM solution, allowing developers to use Entities (an ADO.NET 3.0 feature) to declaratively specify the structure of business objects and use LINQ to query them. LINQ to XML (formerly XLinq) not only augments SQOs but also includes a host of XML-specific features for XML document creation and queries. What You Need to Use LINQLINQ is a combination of extensions to .NET languages and class libraries that support them. To use it, you’ll need the following: Obviously LINQ, which is available from the new Microsoft .NET Framework 3.5 that you can download at http://go.microsoft.com/?linkid=7755937.You can speed up your application development time with LINQ using Visual Studio 2008, which offers visual tools such as LINQ to SQL designer and the Intellisense  support with LINQ’s syntax.Optionally, you can download the Visual C# 2008 Expression Edition tool at www.microsoft.com/vstudio/express/download. It is the free edition of Visual Studio 2008 and offers a lot of LINQ support such as Intellisense and LINQ to SQL designer. To use LINQ to ADO.NET, you need SQL

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  • SQLAuthority News – Download SQL Azure Labs Codename “Data Explorer” Client

    - by pinaldave
    Microsoft SQL Azure labs has recently released Data Explorer client. I was looking forward to visualizing tool for quite a while and I am delighted to see this tool. I will be trying out this tool in coming week and will post here my experience. I have listed few of the resources which are related to Data Explorer at the end. Please let me know if I have missed any and I will add the same. With “Data Explorer” you can: Identify the data you care about from the sources you work with (e.g. Excel spreadsheets, files, SQL Server databases). Discover relevant data and services via automatic recommendations from the Windows Azure Marketplace. Enrich your data by combining it and visualizing the results. Collaborate with your colleagues to refine the data. Publish the results to share them with others or power solutions. The Data Explorer Client package contains the Data Explorer workspace as well as an Office plugin that integrates Data Explorer into Excel. Resources: Download Data Explorer Data Explorer Blog Desktop Client Video of  Contoso Bikes and Frozen Yogurt (Data Explorer) Please note that this is not the final release of the product. Please do not attempt this on production server. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Azure, SQL Documentation, SQL Download, SQL Query, SQL Server, SQL Tips and Tricks, SQLAuthority News, T SQL, Technology

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  • Upgrading log shipping from 2005 to 2008 or 2008R2

    - by DavidWimbush
    If you're using log shipping you need to be aware of some small print. The general idea is to upgrade the secondary server first and then the primary server because you can continue to log ship from 2005 to 2008R2. But this won't work if you're keeping your secondary databases in STANDBY mode rather than IN RECOVERY. If you're using native log shipping you'll have some work to do. If you've rolled your own log shipping (ahem) you can convert a STANDBY database to IN RECOVERY like this:   restore database [dw]   with norecovery; and then change your restore code to use WITH NORECOVERY instead of WITH STANDBY. (Finally all that aggravation pays off!) You can either upgrade the secondary server in place or rebuild it. A secondary database doesn't actually get upgraded until you recover it so the log sequence chain is not broken and you can continue shipping from the primary. Just remember that it can take quite some time to upgrade a database so you need to factor that into the expectations you give people about how long it will take to fail over. For more details, check this out: http://msdn.microsoft.com/en-us/library/cc645954(SQL.105).aspx

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  • Performance and Optimization Isn’t Evil

    - by Reed
    Donald Knuth is a fairly amazing guy.  I consider him one of the most influential contributors to computer science of all time.  Unfortunately, most of the time I hear his name, I cringe.  This is because it’s typically somebody quoting a small portion of one of his famous statements on optimization: “premature optimization is the root of all evil.” I mention that this is only a portion of the entire quote, and, as such, I feel that Knuth is being quoted out of context.  Optimization is important.  It is a critical part of every software development effort, and should never be ignored.  A developer who ignores optimization is not a professional.  Every developer should understand optimization – know what to optimize, when to optimize it, and how to think about code in a way that is intelligent and productive from day one. I want to start by discussing my own, personal motivation here.  I recently wrote about a performance issue I ran across, and was slammed by multiple comments and emails that effectively boiled down to: “You’re an idiot.  Premature optimization is the root of all evil.  This doesn’t matter.”  It didn’t matter that I discovered this while measuring in a profiler, and that it was a portion of my code base that can take “many hours to complete.”  Even so, multiple people instantly jump to “it’s premature – it doesn’t matter.” This is a common thread I see.  For example, StackOverflow has many pages of posts with answers that boil down to (mis)quoting Knuth.  In fact, just about any question relating to a performance related issue gets this quote thrown at it immediately – whether it deserves it or not.  That being said, I did receive some positive comments and emails as well.  Many people want to understand how to optimize their code, approaches to take, tools and techniques they can use, and any other advice they can discover. First, lets get back to Knuth – I mentioned before that Knuth is being quoted out of context.  Lets start by looking at the entire quote from his 1974 paper Structured Programming with go to Statements: “We should forget about small efficiencies, say about 97% of the time: premature optimization is the root of all evil. Yet we should not pass up our opportunities in that critical 3%. A good programmer will not be lulled into complacency by such reasoning, he will be wise to look carefully at the critical code; but only after that code has been identified.” Ironically, if you read Knuth’s original paper, this statement was made in the middle of a discussion of how Knuth himself had changed how he approaches optimization.  It was never a statement saying “don’t optimize”, but rather, “optimizing intelligently provides huge advantages.”  His approach had three benefits: “a) it doesn’t take long” … “b) the payoff is real”, c) you can “be less efficient in the other parts of my programs, which therefore are more readable and more easily written and debugged.” Looking at Knuth’s premise here, and reading that section of his paper, really leads to a few observations: Optimization is important  “he will be wise to look carefully at the critical code” Normally, 3% of your code – three lines out of every 100 you write, are “critical code” and will require some optimization: “we should not pass up our opportunities in that critical 3%” Optimization, if done well, should not be time consuming: “it doesn’t take long” Optimization, if done correctly, provides real benefits: “the payoff is real” None of this is new information.  People who care about optimization have been discussing this for years – for example, Rico Mariani’s Designing For Performance (a fantastic article) discusses many of the same issues very intelligently. That being said, many developers seem unable or unwilling to consider optimization.  Many others don’t seem to know where to start.  As such, I’m going to spend some time writing about optimization – what is it, how should we think about it, and what can we do to improve our own code.

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  • Create my own database system

    - by Xananax
    Ok so before I get bashed: I know it's something huge for one person; I don't care if the end product can actually be used or not. I need to learn how databases work in order to use them more efficiently, and my way of learning is by doing. So I want to create my own database system. I am not referring to creating a pseudo-database that would use query to parse files; this would simply be a filesystem interface with a query language. I am talking about the actual structure of a database engine. And since what I have in mind is neither relational nor document-oriented (it's "node-oriented", if that even exists), I would need any resource to be as abstract and high-level as possible. So how would I go about creating that? What resources/tutorials/books can I read to understand? The language does not matter in the slightest. Ideally, the code would be pseudo-code to illustrate the concept, not tied to a particular language, but anything would do. I was not able to find anything on the matter on google (since I am so illiterate on the subject, maybe I am just not entering the right search). If such resources are not available, then I guess something about how to create a client would at least be a step in the right direction.

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  • Using Oracle Data in the Business Rules Engine

    - by Christopher House
    Yesterday I started working on some new functionality that I had planned to implement using the Business Rules Engine.  As I got further into it, I realized that some of my rules were going to need to reference some data that resides in an Oracle database.  I knew the Business Rules Composer supports using DataConnections and TypedDataTables, but I’d never used this functionality myself, so I wasn’t so sure how it would work with Oracle.  As it turns out, it’s very do-able, there’s just little hoop you need to jump through. I fired up BRC and my suspicions were quickly confirmed.  BRC only recognizes SQL Server databases when it comes to editing rules.  Not letting that deter me, I decided to see if I could “trick” BRE into using Oracle data. On my local SQL server, I created a new database and in that database, created a table that matched the schema of the table I wanted to use in the Oracle database.  I then set about creating my rules, referencing the new SQL Server database everywhere I wanted to use Oracle data.  Finally, I created a new class library and added a class that implements Microsoft.RuleEngine.IFactRetriever.  In that class, I added the necessary code to get a DataSet from the Oracle server, wrap it in a TypedDataTable and assert it into the rule engine.  It’s worth pointing out that in my IFactRetriever class, I made sure to set my DataSet name to the name of the database I’d referenced in the BRC and the DataTable’s name to the name of the table that I’d referenced in the BRC. After gac’ing the new class library and deploying my policy, I tested and everything worked as expected.

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  • Something for the weekend - Whats the most complex query?

    - by simonsabin
    Whenever I teach about SQL Server performance tuning I try can get across the message that there is no such thing as a table. Does that sound odd, well it isn't, trust me. Rather than tables you need to consider structures. You have 1. Heaps 2. Indexes (b-trees) Some people split indexes in two, clustered and non-clustered, this I feel confuses the situation as people associate clustered indexes with sorting, but don't associate non clustered indexes with sorting, this is wrong. Clustered and non-clustered indexes are the same b-tree structure(and even more so with SQL 2005) with the leaf pages sorted in a linked list according to the keys of the index.. The difference is that non clustered indexes include in their structure either, the clustered key(s), or the row identifier for the row in the table (see http://sqlblog.com/blogs/kalen_delaney/archive/2008/03/16/nonclustered-index-keys.aspx for more details). Beyond that they are the same, they have key columns which are stored on the root and intermediary pages, and included columns which are on the leaf level. The reason this is important is that this is how the optimiser sees the world, this means it can use any of these structures to resolve your query. Even if your query only accesses one table, the optimiser can access multiple structures to get your results. One commonly sees this with a non-clustered index scan and then a key lookup (clustered index seek), but importantly it's not restricted to just using one non-clustered index and the clustered index or heap, and that's the challenge for the weekend. So the challenge for the weekend is to produce the most complex single table query. For those clever bods amongst you that are thinking, great I will just use lots of xquery functions, sorry these are the rules. 1. You have to use a table from AdventureWorks (2005 or 2008) 2. You can add whatever indexes you like, but you must document these 3. You cannot use XQuery, Spatial, HierarchyId, Full Text or any open rowset function. 4. You can only reference your table once, i..e a FROM clause with ONE table and no JOINs 5. No Sub queries. The aim of this is to show how the optimiser can use multiple structures to build the results of a query and to also highlight why the optimiser is doing that. How many structures can you get the optimiser to use? As an example create these two indexes on AdventureWorks2008 create index IX_Person_Person on Person.Person (lastName, FirstName,NameStyle,PersonType) create index IX_Person_Person on Person.Person(BusinessentityId,ModifiedDate)with drop_existing    select lastName, ModifiedDate   from Person.Person  where LastName = 'Smith' You will see that the optimiser has decided to not access the underlying clustered index of the table but to use two indexes above to resolve the query. This highlights how the optimiser considers all storage structures, clustered indexes, non clustered indexes and heaps when trying to resolve a query. So are you up to the challenge for the weekend to produce the most complex single table query? The prize is a pdf version of a popular SQL Server book, or a physical book if you live in the UK.  

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  • Silverlight Cream for March 24, 2010 -- #819

    - by Dave Campbell
    In this Issue: Nokola, Tim Heuer, Christian Schormann, Brad Abrams, David Kelley, Phil Middlemiss, Michael Klucher, Brandon Watson, Kunal Chowdhury, Jacek Ciereszko, and Unni. Shoutouts: Michael Klucher has a short post up For Love of the Game (Development)…, where he's looking for some input from the developer community. Shawn Hargreaves has a link post up of all the Windows Phone MIX10 presentations Chris Cavanagh has a Soft-Body Physics for Windows Phone 7 post up that goes along with one he did 1-1/2 years ago! Jeff Weber posted An Open Letter To Microsoft Regarding The Silverlight Game Development Community Pete Brown posted his MIX10 Recap ... lots of information, and discussion of what he was up to ... I liked the Trivia app Pete... glad to hear that was yours :) I've changed my mind and added a WP7 tag to SilverlightCream. I'll straighten out all the Mobile plus Silverlight links to point at the WP7 tab hopefully tonight. From SilverlightCream.com: EasyPainter Source Pack 3: Adorners, Mouse Cursors and Frames Nokola has been busy with EasyPainter adding in Custom, Extensible Mouse Cursors and Customizable Adorners with extensible adorner frames, and best of all... all with source code! Simulate Geo Location in Silverlight Windows Phone 7 emulator Among the things we don't have in our WP7 emulators is Geo Location... Tim Heuer comes to the rescue with a simulator for it... too cool, Tim! Blend 4: About Path Layout, Part II Christian Schormann is back with Part 2 of his tutorial sequence on the new Path Layout. Really good info and definitely cool presentations of the control. Silverlight 4 + RIA Services - Ready for Business: Exposing OData Services Brad Abrams continues his series with a post on exposing OData services. This looks like a great tutorial on the topic... will probably resolve some questions I've been having :) No Silverlight and Preloader Experience(ish) - in 10 seconds... David Kelley exposes the code he uses on his site, designed to be friendly to Silverlight and non-Silverlight users alike. Merged Dictionaries of Style Resources and Blend Phil Middlemiss has a nice article up on Merged Dictionaries and using multiple resource dictionaries that the app chooses, but also be compatible with Prism and Blend while not eating your system resources out of house and home. XNA Game Studio and Windows Phone Emulator Compatibility Michael Klucher has a definitive post up about getting your XNA and system up-to-speed for WP7... a must-read if you've been running any of the other XNA drops. Windows Phone 7 301 Redirect Bug Brandon Watson reports a 301 Redirect bug on WP7 ... see the code and how he got it, then follow along as he explains all the debug paths he took and what the resolution (?) really is :) Silverlight 4: How to use the new Printing API? Kunal Chowdhury has a tutorial up on printing with Silverlight 4 RC... from the project layout to printing and then printing a smaller section... all good Printing problem in Silverlight 4.0 RC - loading images in code behind Jacek Ciereszko also is writing about printing, and in his case he had problems with loading an image dynamically and printing it... plus he provides a solution to the 'blank page' problem. ToolboxExampleAttribute - a new extension point in Blend 4 (and a few other extensibility related changes) Unni has an article up about Expression Blend 4's new ToolboxExampleAttribute which allow you to have multiple examples of the same type resulting in different XAML produced. Stay in the 'Light! Twitter SilverlightNews | Twitter WynApse | WynApse.com | Tagged Posts | SilverlightCream Join me @ SilverlightCream | Phoenix Silverlight User Group Technorati Tags: Silverlight    Silverlight 3    Silverlight 4    Windows Phone    MIX10

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  • Database platform migration from Windows-32bit to Linux-64bit

    - by [email protected]
    We have a customer which have all they core business database on RAC over Windows OS. Last year they were affected by a virus that destroyed the registry and all their RAC environments were "OUT OF ORDER", the result, thousand people on vacation for a day.They were distrustful about Linux and after came an agreement to migrate their Enterprise Manager from Windows to Linux (OMS and Repository). How we did demonstrate how powerful and easy is RMAN to migrate databases across platforms.Fist of check of target platform is available from sourceSQL> select platform_name from v$db_transportable_platform;PLATFORM_NAME-----------------------------------------------------------Microsoft Windows IA (32-bit)Linux IA (32-bit)HP Tru64 UNIXLinux IA (64-bit)HP Open VMSMicrosoft Windows IA (64-bit)Linux 64-bit for AMDMicrosoft Windows 64-bit for AMDSolaris Operating System (x86)Check database object as directories that can change across platforms, also check external tables.Startup source database in read only modeRun the following RMAN ScriptRMAN> connect target / RMAN> convert database on target platform convert script 'c:/temp/convert_grid.rman'transport script 'c:/TEMP/transporta_grid.sql' new database 'gridbd' format 'c:/temp/gridmydb%U' db_file_name_convert 'C:\oracle\oradata\grid','/oracle/gridbd/data2/data';(Notice tha path change on db_file_name_convert)Move from source to target:PfileNew scriptsexternal table filesbfilesdata filesCheck pfile, and ensure that the paths are OKCreate temporary control file to connect rmanExecute the RMAN scriptRMAN> connect target / RMAN> @/home/oracle/pboixeda/win2lnx.rmanShutdown the instance and remove temporary control filesRecreate controlfile/s, take care about the used paths.Execute the transport script, transporta_grid.sqlDue we were moving from a 32-bit architecture to a 64-bit architecture, there is bug reported in 386990.1 note, we had to recreate OLAP , check the note for more details. Alter or Recreate all necessary objects Launch utlrpAfter this experience with Linux they are on the way to migrate all their RAC from 10gR2 on Windows to 11gR2 Linux 64 bit.Hope it helps

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  • SQL SERVER – Online Session on What is New in Denali – Today Online

    - by pinaldave
    I will be presenting today on subject Inside of Next Generation SQL Server – Denali online at Zeollar.com. This sessions are really fun as they are online, downloadable, and 100% demo oriented. I will be using SQL Server ‘Denali’ CTP 1 to present on the subject of What is New in Denali. The webcast will start at 12:30 PM sharp and will end at 1 PM India Time. It will be 100% demo oriented and no slides. I will be covering following topics in the session. SQL SERVER – Denali Feature – Zoom Query Editor SQL SERVER – Denali – Improvement in Startup Options SQL SERVER – Denali – Clipboard Ring – CTRL+SHIFT+V SQL SERVER – Denali – Multi-Monitor SSMS Windows SQL SERVER – Denali – Executing Stored Procedure with Result Sets SQL SERVER – Performance Improvement with of Executing Stored Procedure with Result Sets in Denali SQL SERVER – ‘Denali’ – A Simple Example of Contained Databases SQL SERVER – Denali – ObjectID in Negative – Local TempTable has Negative ObjectID SQL SERVER – Server Side Paging in SQL Server Denali – A Better Alternative SQL SERVER – Server Side Paging in SQL Server Denali Performance Comparison SQL SERVER – Denali – SEQUENCE is not IDENTITY SQL SERVER – Denali – Introduction to SEQUENCE – Simple Example of SEQUENCE If time permits we will cover few more topics as well. The session will be recorded as well. My earlier session on the Topic of Best Practices Analyzer is also available to watch online here: SQL SERVER – Video – Best Practices Analyzer using Microsoft Baseline Configuration Analyzer Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQLServer, T SQL, Technology

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  • Upgrade to 11.2.0.3 - OCM: ORA-12012 and ORA-29280

    - by Mike Dietrich
    OCM is the Oracle Configuration Manager, a tool to proactively monitor your Oracle environment to provide this information to Oracle Software Support. As OCM is installed by default in many databases but is some sort of independent from the database's version you won't expect any issues during or after a database upgrade But after the upgrade from Oracle 11.1.0.7 to Oracle 11.2.0.3 on Exadata X2-2 one of my customers found the following error in the alert.log every 24 hours: Errors in file /opt/oracle/diag/rdbms/db/trace/db_j001_26027.trc: ORA-12012: error on auto execute of job "ORACLE_OCM"."MGMT_CONFIG_JOB_2_1" ORA-29280: invalid directory path ORA-06512: at "ORACLE_OCM.MGMT_DB_LL_METRICS", line 2436 ORA-06512: at line 1 Why is that happening and how to solve that issue now? OCM is trying to write to a local directory which does not exist. Besides that the OCM version delivered with Oracle Database Patch Set 11.2.0.3 is older than the newest available OCM Collector 10.3.7 - the one which has that issue fixed. So you'll either drop OCM completely if you won't use it: SQL> drop user ORACLE_OCM cascade; or you'll disable the collector jobs: SQL> exec dbms_scheduler.disable('ORACLE_OCM.MGMT_CONFIG_JOB');SQL> exec dbms_scheduler.disable('ORACLE_OCM.MGMT_STATS_CONFIG_JOB'); or you'll have to reconfigure OCM - and please see MOS Note:1453959.1 for a detailed description how to do that - it's basically executing the script ORACLE_HOME/ccr/admin/scripts/installCCRSQL - but there maybe other things to consider especially in a RAC environment. - Mike

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  • T-SQL Improvements And Data Types in ms sql 2008

    - by Aamir Hasan
     Microsoft SQL Server 2008 is a new version released in the first half of 2008 introducing new properties and capabilities to SQL Server product family. All these new and enhanced capabilities can be defined as the classic words like secure, reliable, scalable and manageable. SQL Server 2008 is secure. It is reliable. SQL2008 is scalable and is more manageable when compared to previous releases. Now we will have a look at the features that are making MS SQL Server 2008 more secure, more reliable, more scalable, etc. in details.Microsoft SQL Server 2008 provides T-SQL enhancements that improve performance and reliability. Itzik discusses composable DML, the ability to declare and initialize variables in the same statement, compound assignment operators, and more reliable object dependency information. Table-Valued ParametersInserts into structures with 1-N cardinality problematicOne order -> N order line items"N" is variable and can be largeDon't want to force a new order for every 20 line itemsOne database round-trip / line item slows things downNo ARRAY data type in SQL ServerXML composition/decomposition used as an alternativeTable-valued parameters solve this problemTable-Valued ParametersSQL Server has table variablesDECLARE @t TABLE (id int);SQL Server 2008 adds strongly typed table variablesCREATE TYPE mytab AS TABLE (id int);DECLARE @t mytab;Parameters must use strongly typed table variables Table Variables are Input OnlyDeclare and initialize TABLE variable  DECLARE @t mytab;  INSERT @t VALUES (1), (2), (3);  EXEC myproc @t;Procedure must declare variable READONLY  CREATE PROCEDURE usetable (    @t mytab READONLY ...)  AS    INSERT INTO lineitems SELECT * FROM @t;    UPDATE @t SET... -- no!T-SQL Syntax EnhancementsSingle statement declare and initialize  DECLARE @iint = 4;Compound Assignment Operators  SET @i += 1;Row constructors  DECLARE @t TABLE (id int, name varchar(20));  INSERT INTO @t VALUES    (1, 'Fred'), (2, 'Jim'), (3, 'Sue');Grouping SetsGrouping Sets allow multiple GROUP BY clauses in a single SQL statementMultiple, arbitrary, sets of subtotalsSingle read pass for performanceNested subtotals provide ever better performanceGrouping Sets are an ANSI-standardCOMPUTE BY is deprecatedGROUPING SETS, ROLLUP, CUBESQL Server 2008 - ANSI-syntax ROLLUP and CUBEPre-2008 non-ANSI syntax is deprecatedWITH ROLLUP produces n+1 different groupings of datawhere n is the number of columns in GROUP BYWITH CUBE produces 2^n different groupingswhere n is the number of columns in GROUP BYGROUPING SETS provide a "halfway measure"Just the number of different groupings you needGrouping Sets are visible in query planGROUPING_ID and GROUPINGGrouping Sets can produce non-homogeneous setsGrouping set includes NULL values for group membersNeed to distinguish by grouping and NULL valuesGROUPING (column expression) returns 0 or 1Is this a group based on column expr. or NULL value?GROUPING_ID (a,b,c) is a bitmaskGROUPING_ID bits are set based on column expressions a, b, and cMERGE StatementMultiple set operations in a single SQL statementUses multiple sets as inputMERGE target USING source ON ...Operations can be INSERT, UPDATE, DELETEOperations based onWHEN MATCHEDWHEN NOT MATCHED [BY TARGET] WHEN NOT MATCHED [BY SOURCE]More on MERGEMERGE statement can reference a $action columnUsed when MERGE used with OUTPUT clauseMultiple WHEN clauses possible For MATCHED and NOT MATCHED BY SOURCEOnly one WHEN clause for NOT MATCHED BY TARGETMERGE can be used with any table sourceA MERGE statement causes triggers to be fired onceRows affected includes total rows affected by all clausesMERGE PerformanceMERGE statement is transactionalNo explicit transaction requiredOne Pass Through TablesAt most a full outer joinMatching rows = when matchedLeft-outer join rows = when not matched by targetRight-outer join rows = when not matched by sourceMERGE and DeterminismUPDATE using a JOIN is non-deterministicIf more than one row in source matches ON clause, either/any row can be used for the UPDATEMERGE is deterministicIf more than one row in source matches ON clause, its an errorKeeping Track of DependenciesNew dependency views replace sp_dependsViews are kept in sync as changes occursys.dm_sql_referenced_entitiesLists all named entities that an object referencesExample: which objects does this stored procedure use?sys.dm_sql_referencing_entities 

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  • Agile PLM Partners and OCS offer valuable services

    - by Shane Goodwin
    One of the amazing benefits of using Agile is the ability to tap into a broad number of Partners and Oracle Consulting Services to leverage very talented people. Many of these people respond to postings on the Agile PLM Yahoo usergroups (WRAU and IAUG) as well as in the Oracle Support Community. As you are managing your Agile PLM project, either a new implementation or an upgrade, these Partners and OCS can jumpstart your internal resources with information and experience which takes years to develop. They can also offer other capabilities which add to your Agile experience. As an example, GoEngineer recently announced a new offering to host Agile PLM databases for companies who do not want to run their own Agile PLM system. This offering provides our smaller customers with more options on how to implement Agile PLM. The Oracle Consulting Services group has two new offerings, one for Rapid Deployments of new customers and another for Process and Technical Diagnostics of existing customers in order to better leverage the PLM investment. Contact your Oracle Sales representative to learn more. In addition, there are many other partners who are helping our customers get the most from Agile PLM. Some examples are below. In the coming months, the Oracle Partner Network will be working with partners to certify them as specialists in Agile PLM. Some of our other current partners working on Agile PLM are: Kalypso J Squared Domain Systems Sierra Atlantic Minerva

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  • SQLAuthority Book Review – DBA Survivor: Become a Rock Star DBA

    - by pinaldave
    DBA Survivor: Become a Rock Star DBA – Thomas LaRock Link to Amazon Link to Flipkart First of all, I thank all my readers when I wrote that I could not get this book in any local book stores, because they offered me to send a copy of this good book. A very special mention goes to Sripada and Jayesh for they gave so much effort in finding my home address and sending me the hard copy. Before, I did not have the copy of the book, but now I have two of it already! It surprises me how my readers were able to find my home address, which I have not publicly shared. Quick Review: This is indeed a one easy-to-read and fun book. We all work day and night with technology yet we should not forget to show our love and care for our family at home. For our souls that starve for peace and guidance, this one book is the “it” book for all the technology enthusiasts. Though this book was specifically written for DBAs, the reach is not limited to DBAs only because the lessons incorporated in it actually applies to all. This is one of the most motivating technical books I have read. Detailed Review: Let us go over a few questions first: Who wants to be as famous as rockstars in the field of Database Administration? How can one learn what it takes to become a top notch software developer? If you are a beginner in your field, how will you go to next level? Your boss may be very kind or like Dilbert’s Boss, what will you do? How do you keep growing when Eco-system around you does not support you? You are almost at top but there is someone else at the TOP, what do you do and how do you avoid office politics? As a database developer what should be your basic responsibility? and many more… I was able to completely read book in one sitting and I loved it. Before I continue with my opinion, I want to echo the opinion of Kevin Kline who has written the Forward of the book. He has truly suggested that “You hold in your hands a collection of insights and wisdom on the topic of database administration gained through many years of hard-won experience, long nights of study, and direct mentorship under some of the industry’s most talented database professionals and information technology (IT) experts.” Today, IT field is getting bigger and better, while talking about terabytes of the database becomes “more” normal every single day. The gods and demigods of database professionals are taking care of these large scale databases and are carefully maintaining them. In this world, there are only a few beginnings on the first step. There are many experts in different technology fields who are asked to address the issues with databases. There is YOU and ME, who is just new to this work. So we ask ourselves WHERE to begin and HOW to begin. We adore and follow the religion of our rockstars, but oftentimes we really have no idea about their background and their struggles. Every rockstar has his success story which needs to be digested before learning his tricks and tips. This book starts with the same note and teaches the two most important lessons for anybody who wants to be a DBA Rockstar –  to focus on their single goal of learning and to excel the technology. The story starts with three simple guidelines – Get Prepared, Get Trained, Get Certified. Once a person learns the skills, and then, it would be about time that he needs to enrich or to improve those skills you have learned. I am sure that the right opportunity will come finding themselves and they will not have to go run behind it. However, the real challenge for any person is the first day or first week. A new employee, no matter how much experienced he is, sometimes has no clue about what should one do at new job. Chapter 2 and chapter 3 precisely talk about what one should do as soon as the new job begins. It is also written with keeping the fact in focus that each job can be very much different but there are few infrastructure setups and programming concepts are the same. Learning basics of database was really interesting. I like to focus on the roots of any technology. It is important to understand the structure of the database before suggesting what indexes needs to be created, the same way this book covers the most essential knowledge one must learn by most database developers. I think the title of the fourth chapter is my favorite sentence in this book. I can see that I will be saying this again and again in the future – “A Development Server Is a Production Server to a Developer“. I have worked in the software industry for almost 8 years now and I have seen so many developers sitting on their chairs and waiting for instructions from their lead about how to improve the code or what to do the next. When I talk to them, I suggest that the experiment with their server and try various techniques. I think they all should understand that for them, a development server is their production server and needs to pay proper attention to the code from the beginning. There should be NO any inappropriate code from the beginning. One has to fully focus and give their best, if they are not sure they should ask but should do something and stay active. Chapter 5 and 6 talks about two essential skills for any developer and database administration – what are the ethics of developers when they are working with production server and how to support software which is running on the production server. I have met many people who know the theory by heart but when put in front of keyboard they do not know where to start. The first thing they do opening the browser and searching online, instead of opening SQL Server Management Studio. This can very well happen to anybody who is experienced as well. Chapter 5 and 6 addresses that situation as well includes the handy scripts which can solve almost all the basic trouble shooting issues. “Where’s the Buffet?” By far, this is the best chapter in this book. If you have ever met me, you would know that I love food. I think after reading this chapter, I felt Thomas has written this just keeping me in mind. I think there will be many other people who feel the same way, too. Even my wife who read this chapter thought this was specifically written for me. I will not talk any more about this chapter as this is one must read chapter. And of course this is about real ‘FOOD‘. I am an SQL Server Trainer and Consultant and I totally agree with the point made in the chapter 8 of this book. Yes, it says here that what is necessary to train employees and people. Millions of dollars worth the labor is continuously done in the world which has faults and incorrect. Once something goes wrong, very expensive consultant comes in and fixes the problem. This whole cycle which can be stopped and improved if proper training is done. There is plenty of free trainings available as well, if one cannot afford paid training. “Connect. Learn. Share” – I think this is a great summary and bird’s eye view of this book. Networking is the key. Everything which is discussed in this book can be taken to next level if one properly uses this tips and continuously grow with it. Connecting with others, helping learn each other and building the good knowledge sharing environment should be the goal of everyone. Before I end the review I want to share a real experience. I have personally met one DBA who has worked in a single department in a company for so long that when he was put in a different department in his company due to closing that department, he could not adjust and quit the job despite the same people and company around him. Adjusting in the new environment gets much tougher as one person gets more and more experienced. This book precisely addresses the same issue along with their solutions. I just cannot stop comparing the book with my personal journey. I found so many things which are coincidently in the book is written as how we developer and DBA think. I must express special thanks to Thomas for taking time in his personal life and write this book for us. This book is indeed a book for everybody who wants to grow healthy in the tough and competitive environment. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQLAuthority Book Review, SQLAuthority News, SQLServer, T SQL, Technology

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  • SQL SERVER – Reducing CXPACKET Wait Stats for High Transactional Database

    - by pinaldave
    While engaging in a performance tuning consultation for a client, a situation occurred where they were facing a lot of CXPACKET Waits Stats. The client asked me if I could help them reduce this huge number of wait stats. I usually receive this kind of request from other client as well, but the important thing to understand is whether this question has any merits or benefits, or not. Before we continue the resolution, let us understand what CXPACKET Wait Stats are. The official definition suggests that CXPACKET Wait Stats occurs when trying to synchronize the query processor exchange iterator. You may consider lowering the degree of parallelism if a conflict concerning this wait type develops into a problem. (from BOL) In simpler words, when a parallel operation is created for SQL Query, there are multiple threads for a single query. Each query deals with a different set of the data (or rows). Due to some reasons, one or more of the threads lag behind, creating the CXPACKET Wait Stat. Threads which came first have to wait for the slower thread to finish. The Wait by a specific completed thread is called CXPACKET Wait Stat. Note that CXPACKET Wait is done by completed thread and not the one which are unfinished. “Note that not all the CXPACKET wait types are bad. You might experience a case when it totally makes sense. There might also be cases when this is also unavoidable. If you remove this particular wait type for any query, then that query may run slower because the parallel operations are disabled for the query.” Now let us see what the best practices to reduce the CXPACKET Wait Stats are. The suggestions, with which you will find that if you search online through the browser, would play a major role as and might be asked about their jobs In addition, might tell you that you should set ‘maximum degree of parallelism’ to 1. I do agree with these suggestions, too; however, I think this is not the final resolutions. As soon as you set your entire query to run on single CPU, you will get a very bad performance from the queries which are actually performing okay when using parallelism. The best suggestion to this is that you set ‘the maximum degree of parallelism’ to a lower number or 1 (be very careful with this – it can create more problems) but tune the queries which can be benefited from multiple CPU’s. You can use query hint OPTION (MAXDOP 0) to run the server to use parallelism. Here is the two-quick script which helps to resolve these issues: Change MAXDOP at Server Level EXEC sys.sp_configure N'max degree of parallelism', N'1' GO RECONFIGURE WITH OVERRIDE GO Run Query with all the CPU (using parallelism) USE AdventureWorks GO SELECT * FROM Sales.SalesOrderDetail ORDER BY ProductID OPTION (MAXDOP 0) GO Below is the blog post which will help you to find all the parallel query in your server. SQL SERVER – Find Queries using Parallelism from Cached Plan Please note running Queries in single CPU may worsen your performance and it is not recommended at all. Infect this can be very bad advise. I strongly suggest that you identify the queries which are offending and tune them instead of following any other suggestions. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: SQL, SQL Authority, SQL Optimization, SQL Performance, SQL Query, SQL Server, SQL Tips and Tricks, SQL White Papers, SQLAuthority News, T SQL, Technology

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  • SQL SERVER – Merge Operations – Insert, Update, Delete in Single Execution

    - by pinaldave
    This blog post is written in response to T-SQL Tuesday hosted by Jorge Segarra (aka SQLChicken). I have been very active using these Merge operations in my development. However, I have found out from my consultancy work and friends that these amazing operations are not utilized by them most of the time. Here is my attempt to bring the necessity of using the Merge Operation to surface one more time. MERGE is a new feature that provides an efficient way to do multiple DML operations. In earlier versions of SQL Server, we had to write separate statements to INSERT, UPDATE, or DELETE data based on certain conditions; however, at present, by using the MERGE statement, we can include the logic of such data changes in one statement that even checks when the data is matched and then just update it, and similarly, when the data is unmatched, it is inserted. One of the most important advantages of MERGE statement is that the entire data are read and processed only once. In earlier versions, three different statements had to be written to process three different activities (INSERT, UPDATE or DELETE); however, by using MERGE statement, all the update activities can be done in one pass of database table. I have written about these Merge Operations earlier in my blog post over here SQL SERVER – 2008 – Introduction to Merge Statement – One Statement for INSERT, UPDATE, DELETE. I was asked by one of the readers that how do we know that this operator was doing everything in single pass and was not calling this Merge Operator multiple times. Let us run the same example which I have used earlier; I am listing the same here again for convenience. --Let’s create Student Details and StudentTotalMarks and inserted some records. USE tempdb GO CREATE TABLE StudentDetails ( StudentID INTEGER PRIMARY KEY, StudentName VARCHAR(15) ) GO INSERT INTO StudentDetails VALUES(1,'SMITH') INSERT INTO StudentDetails VALUES(2,'ALLEN') INSERT INTO StudentDetails VALUES(3,'JONES') INSERT INTO StudentDetails VALUES(4,'MARTIN') INSERT INTO StudentDetails VALUES(5,'JAMES') GO CREATE TABLE StudentTotalMarks ( StudentID INTEGER REFERENCES StudentDetails, StudentMarks INTEGER ) GO INSERT INTO StudentTotalMarks VALUES(1,230) INSERT INTO StudentTotalMarks VALUES(2,255) INSERT INTO StudentTotalMarks VALUES(3,200) GO -- Select from Table SELECT * FROM StudentDetails GO SELECT * FROM StudentTotalMarks GO -- Merge Statement MERGE StudentTotalMarks AS stm USING (SELECT StudentID,StudentName FROM StudentDetails) AS sd ON stm.StudentID = sd.StudentID WHEN MATCHED AND stm.StudentMarks > 250 THEN DELETE WHEN MATCHED THEN UPDATE SET stm.StudentMarks = stm.StudentMarks + 25 WHEN NOT MATCHED THEN INSERT(StudentID,StudentMarks) VALUES(sd.StudentID,25); GO -- Select from Table SELECT * FROM StudentDetails GO SELECT * FROM StudentTotalMarks GO -- Clean up DROP TABLE StudentDetails GO DROP TABLE StudentTotalMarks GO The Merge Join performs very well and the following result is obtained. Let us check the execution plan for the merge operator. You can click on following image to enlarge it. Let us evaluate the execution plan for the Table Merge Operator only. We can clearly see that the Number of Executions property suggests value 1. Which is quite clear that in a single PASS, the Merge Operation completes the operations of Insert, Update and Delete. I strongly suggest you all to use this operation, if possible, in your development. I have seen this operation implemented in many data warehousing applications. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, SQL, SQL Authority, SQL Joins, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: Merge

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