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  • SQL Server 2008 Cluster Installation - First network name always fails

    - by boflynn
    I'm testing failover clustering in Windows Server 2008 to host a SQL Server 2008 installation using this installation guide. My base cluster is installed and working properly, as well as clustering the DTC service. However, when it comes time to install SQL Server, my first attempt at installation always fails with the same message and seems to "taint" the network name. For example, with my previous cluster attempt, I was installing SQL Server as VSQL. After approximately 15 attempts of installation and trying to resolve the errors, e.g. changing domain accounts for SQL, setting SPNs, etc., I typoed the network name as VQSL and the installation worked. Similarly on my current cluster, I tried installing with the SQL service named PROD-C1-DB and got the same errors as last time until I tried changing the name to anything else, e.g. PROD-C1-DB1, SQL, TEST, etc., at which point the install works. It will even install to VSQL now. While testing, my install routine was: Run setup.exe from patched media, selecting appropriate options After the install fails, I'd chose "Remove node from a SQL Server failover cluster" and remove the single, failed, node Attempt to diagnose problem, inspect event logs, etc. Delete the computer account that was created for the SQL Service from Active Directory Delete the MSSQL10.MSSQLSERVER folder from the shared data drive The error message I receive from the SQL Server installer is: The following error has occurred: The cluster resource 'SQL Server' could not be brought online. Error: The group or resource is not in the correct state to perform the requested operation. (Exception from HRESULT: 0x8007139F) Along with hundreds of the following errors in the Application event log: [sqsrvres] checkODBCConnectError: sqlstate = 28000; native error = 4818; message = [Microsoft][SQL Server Native Client 10.0][SQL Server]Login failed for user 'NT AUTHORITY\ANONYMOUS LOGON'. System configuration notes: Windows Server 2008 Enterprise Edition x64 SQL Server 2008 Enterprise Edition x64 using slipstreamed SP1+CU1 media Dell PowerEdge servers Fibre attached storage

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  • SQL Server 2008 - Shrinking the Transaction Log - Any way to automate?

    - by Albert
    I went in and checked my Transaction log the other day and it was something crazy like 15GB. I ran the following code: USE mydb GO BACKUP LOG mydb WITH TRUNCATE_ONLY GO DBCC SHRINKFILE(mydb_log,8) GO Which worked fine, shrank it down to 8MB...but the DB in question is a Log Shipping Publisher, and the log is already back up to some 500MB and growing quick. Is there any way to automate this log shrinking, outside of creating a custom "Execute T-SQL Statement Task" Maintenance Plan Task, and hooking it on to my log backup task? If that's the best way then fine...but I was just thinking that SQL Server would have a better way of dealing with this. I thought it was supposed to shrink automatically whenever you took a log backup, but that's not happening (perhaps because of my log shipping, I don't know). Here's my current backup plan: Full backups every night Transaction log backups once a day, late morning (maybe hook the Log shrinking onto this...doesn't need to be shrank every day though) Or maybe I just run it once a week, after I run a full backup task? What do you all think?

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  • MSBuild / PowerShell: Copy SQL Server 2012 database to SQL Azure via BACPAC (for Continuous Integration)

    - by giveme5minutes
    I'm creating a continuous integration MSBuild script which copies a database in on-premise SQL Server 2012 to SQL Azure. Easy right? Methods After a fair bit of research I've come across the following methods: Use PowerShell to access the DAC library directly, then use the MSBuild PowerShell extension to wrap the script. This would require installing PowerShell 3 and working out how to make the MSBuild PowerShell extension work with it, as apparently MS moved the DAC API to a different namespace in the latest version of the library. PowerShell would give direct access to the API, but may require quite a bit of boilerplate. Use the sample DAC Framework Client Side Tools, which requires compiling them myself, as the downloads available from Codeplex only include the Hosted version. It would also require fixing them to use DAC 3.0 classes as they appear to currently use an earlier version of DAC. I could then call these tools from an <Exec Command="" /> in the MSBuild script. Less boilerplate and if I hit any bumps in the road I can just make changes to the source. Processes Using whichever method, the process could be either: Export from on-premise SQL Server 2012 to local BACPAC Upload BACPAC to blog storage Import BACPAC to SQL Azure via Hosted DAC Or: Export from on-premise SQL Server 2012 to local BACPAC Import BACPAC to SQL Azure via Client DAC Question All of the above seems to be quite a lot of effort for something that seems to be a standard feature... so before I start reinventing the wheel and documenting the results for all to see, is there something really obvious that I've missed here? Is there pre-written script that MS has released that I have not yet uncovered? There's an command in the GUI of SQL Server Management Studio 2012 that does EXACTLY what I'm trying to do (right click on local database, click "Tasks", click "Deploy Database to SQL Azure"). Surely if it's a few clicks in the GUI it must be a single command on the command line somewhere??

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  • Enabling Session State in SharePoint 2010?

    - by Steve Danner
    I have a web service built for SharePoint 2007 that I am trying to port to SharePoint 2010. This web service is dependent on session state to function properly, but so far, I have been enable to get session state to work at all in SharePoint 2010. This web service runs as its own web application under t he /_vti_bin virtual directory. I have tried all of the following with no luck: Ensured the "State Service" service application is running. Added the System.Web.SessionState.SessionStateModule http module to my application's web.config file. Added the System.Web.SessionState.SessionStateModule http module to my SharePoint root web.config file. Added <pages enableSessionState="true" /> to my application's web.config file. Added <pages enableSessionState="true" /> to my root web.config file. Additional Environment info: Visual Studio 2008 - SP1 .NET 3.5 - SP1 SharePoint 2010 - RC Windows Server 2008 R2 ASMX web service (not WCF) Had anyone had any luck getting a web application or web service to use session state in SharePoint 2010 yet? Thanks! Steve

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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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  • Introducing SSIS Reporting Pack for SQL Server code-named Denali

    - by jamiet
    In recent blog posts I have introduced the new SSIS Catalog that is forthcoming in SQL Server Code-named Denali: What's new in SSIS in Denali Introduction to SSIS Projects in Denali Parameters in SSIS In Denali SSIS Server, Catalogs, Environments and Environment Variables in SSIS in Denali The SSIS Catalog is responsible for executing SSIS packages and also for capturing the metadata from those executions. However, at the time of writing there is no mechanism provided to view analyse and drill into that metadata and that is the reason that I am, in this blog post, introducing a suite of SSIS Catalog reports called the SSIS Reporting Pack which you can download from my SkyDrive at http://cid-550f681dad532637.office.live.com/self.aspx/Public/SSIS%20Reporting%20Pack/SSISReportingPack%20v0.1.zip. In this first release the SSIS Reporting Pack includes five reports: Catalog – A high-level summary of all activity in the Catalog Folders – A summary of activity in each Catalog Folder Folder – Project-level activity per single Folder Executions – A visualisation of all executions per Folder/Project/Package/Environment or subset thereof Execution – Information about an individual execution Here is a screenshot of the Executions report: Notice that the SSIS Reporting Pack provides a visual overview of all executions in the Catalog. Each execution is represented as a bar on the bar chart, the success or otherwise of each execution is indicated by the colour of the bar and the execution time is indicated by the bar height. I have recorded a video that gives an overview of the SSIS Reporting which I have embedded below. If you are having any trouble viewing the video go see it at http://vimeo.com/17617974 I must stress that this is a very early version of the SSIS Reporting Pack and I am expecting it to change a lot over the coming year. I am very keen to get some feedback about this, specifically: let me know if anything does not work as you expect give me your feature requests The easiest way to get hold of of me for now is within the comments section of this blog post. That’s all for now. I hope the SSIS Reporting Pack proves useful and I look forward to hearing your feedback. Lastly, that download link again: http://cid-550f681dad532637.office.live.com/self.aspx/Public/SSIS%20Reporting%20Pack/SSISReportingPack%20v0.1.zip. @jamiet

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  • SQL Server 2008 R2 Installation and the Phantom of SQL Server 2005 Express

    - by Davide Mauri
    Today I’ve happy started to install SQL Server 2008R2 on my development machine, which has this software installed Windows Server 2008 R2 Standard SQL Server 2008 SP1 CU5 Visual Studio 2008 SP1 BOL October 2009 AdventuresWorks2008 Databases SR4 Visual Studio 2010 RTM So, all the basic standard stuff. SQL Server 2008 R2 installation went smooth ‘till somewhere in the middle, where the rule engine checks that software pre-requisite are satisfied before starting to copy files. Here I had this @][@@[?!?! error: “The SQL Server 2005 Express Tools are installed. To continue, remove the SQL Server 2005 Express Tools.” Fun enough, I don’t have and I’ve never had SQL Server 2005 Express on my machine. Armed with patience I analyzed the install log here C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap\Log\yyyymmdd_hhmmss\Detail.txt and I’ve found that the rule “Sql2005SsmsExpressFacet” is the one in charge of this check and it look for existance of the registry key HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\90\Tools\ShellSEM (on x86) HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Microsoft SQL Server\90\Tools\ShellSEM (on x64) In my registry I’ve found that key existsing, due to the installation of the uber-cool Red-Gate SQL Search. I removed the registry key and here it is! SQL Server 2008 R2 is installing while I’m writing this post. A note to Microsoft: can you please add more detailed information on the setup while such error happens. Just saying “you have SQL Server 2005 Express installed” is not enough. Please show us what the rule look for and why it has failed directly in the Detailed Report, so that we don’t have to spend time to look for the needle in the logs. Thanks! :) PS I did a side-by-side installation with the existing SQL Server 2008 instance. Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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  • UPK Content State

    - by peter.maravelias
    State is an editable property for communicating the status of a document in the UPK library. This is particularly helpful when working with other authors in a development team. Authors can assign a state to any document using the values that are defined in the master list. The default master list of State values includes Not Started, Draft, In Review, and Final (in the language installed on the server). Administrators can customize the list by adding, deleting, or renaming the values as well as sequencing the values as they will appear on the assignment list from the Properties pane. Let us know if or how you are using UPK Content States in your development efforts!

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  • Six in Six - SQL Server 2012 Webinars

    - by JustinL
    We're running six webinars over the next six months covering our experiences with SQL Server 2012 and customer deployments. I'm presenting the first on upgrading to SQL Server 2012 next month, subsequent sessions will be delivered by colleagues: NOVEMBER: SQL Server 2012 Upgrade Approach and considerations. Friday 23rd November 12:00 – 13:00 Present approaches for upgrade testing, managing risk and rollback. The session will include details on minimizing downtime and upgrading from SQL Server 2000, 2005, and 2008 including.... More details and register. DECEMBER: Delivering Mission Critical BI with SQL Server 2012– Friday 14th December 12:00-13:00 Information is the lifeblood of many organisations and the availability of timely, accurate information is critical to strategic decision making. This session covers the features and capabilities… More details and register. JANUARY: Architecting Highly Available solutions with SQL Server 2012 – Friday 18th January 12:00- 13:00 Overview and comparison of the high availability features available within SQL Server 2012. The session considers business requirements for availability and recoverability and presents a number of alternative solution designs to meet… More details and register. FEBRUARY: Private cloud deployments with SQL Server 2012 – Friday 15th February 12:00- 13:00 Cloud based technology provide cost effective scale and flexibility. This session provides an overview of the benefits organisations can realise through private cloud… More details and register. MARCH: Visualising data patterns with SQL Server 2012 – Friday 22nd March 12:00- 13:00 This webinar demonstrates the ease of delivering business insight by exploring information and identifying trends through data visualisation. SQL Server 2012 provides new capability with enhanced performance and … More details and register. APRIL: Architecting Highly Available solutions with SQL Server 2012 – Friday 26th April 12:00- 13:00 Customers are increasingly interested in leveraging the benefits of cloud based solutions to provide scalable and flexible infrastructure to host their applications. This session looks at common design patterns and workloads… More details and register. Justin Langford - Coeo Ltd SQL Server Consultants | SQL Server Remote DBA

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  • extrapolating object state based on updates

    - by user494461
    I have a networked multi-user collaborative application. To maintain a consistent virtual world, I send updates for objects from a master peer to a guest peer. The update state contains x,y,z coordinates of object center and his rotation matrix(CHAI3d api used a 3x3 matrix) with 30Hz frequency. I want to reduce this update rate and want to send with a reduced update rate. I want a predictor on both peers. When the predicted value is outside, say a error value of 10% in comparison to master peers objects original state the master peer triggers a state update. Now for position I used velocity,position updates so that the guest peer can extrapolate position. Like velocity for position what parameter should I use for rotation extrapolition?

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  • Oracle SQL Developer: Fetching SQL Statement Result Sets

    - by thatjeffsmith
    Running queries, browsing tables – you are often faced with many thousands, if not millions, of rows. Most people are happy with looking at the first few rows. But occasionally you need to see more. SQL Developer doesn’t show you all records, all at once. Instead, it brings the records down in ‘chunks,’ or as-needed. How It Works There is a preference that tells SQL Developer how many records to get in a single request, or ‘fetch’ of records. The default is 50… So if I run a query that returns MORE than 50 rows: There’s more than 50 records in this resultset, but we have 50 in the grid to start with. We don’t know how many records are in this result set actually. To show the record count here, we actually go physically query the database with a row count type query. All we know is that the query has finished executing, and that there are rows available to go fetch. It tells us when it’s done. As you scroll through the grid, if you get to record 50 and scroll more, we’ll get 50 more records. Or, you can cheat to get to the ‘bottom’ of the result set. You can ask SQL Developer to just to get all the records at once… Once all the records have been fetched, you’ll see this: All rows fetched! A word of caution There’s a reason we have the default set to 50 and not 1000. Bringing back data can get expensive and heavy. We’ve found the best performance to be found in that 50 to 200 record range.

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  • Text reverses on remote gnome session

    - by Andrew Stern
    I have two computers running 10.4 . The first machine is a wired desktop with sshd. The second is a wifi connected laptop with the ssh client. When I use my laptop to bring up a remote gnome session to my desktop all the text gets reversed. Steps: 1) login as a user on the laptop to activate the wifi with a stored key. 2) goto a console Ctrl-Alt F1 3) do a xterm -- :1 to bring up a blank graphic session 4) ssh -Y user@desktopmachine gnome-session This shows reversed text and messes up the keyboard so I can't type

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  • Autostart desktop applications without session login

    - by derekcentrico
    I understand the idea of startup applications when starting a session (ie How do I start a program automatically when I boot?). However, I'm trying to have desktop applications for multiple users start when the computer reboots/starts. Some apps I'm aiming for are Google Music Manager, remote desktop server for each session, etc. How can I either have multiple user sessions launch on boot to get these apps going -or- have them launch some other way for those users? Right now I have my primary user automatically login to start its session and related apps...

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  • Moving from a traditional in memory Java session to persistent storage sessions

    - by Benju
    We have decided to take the plunge and move from using a typical java session provider in Tomcat/Jetty/etc to persisting everything to a central datastore. We are looking at using MongoDB for this. A few options come to mind... http://wiki.eclipse.org/Jetty/Tutorial/MongoDB_Session_Clustering This is nice because it will "auto-magically" persist our session to a Mongo installation. I am concerned however that we will not have fine grained control of what is happening. https://github.com/mattinsler/com.lowereast.guiceymongo/ GuiceMongo is interesting as it integrates with Guice. Perhaps we could persist everything via this ORM. Has anybody had to deal with this kind of move? It seems that moving from in memory to persistent session storage has a lot of gotchas.

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  • session persisting problem after system restart

    - by user100124
    Is there a way to prevent session id restore on startup/restart of user's system? We are using a asp.net app and I am able to login and access the site. For the first time session id is created and stored in cookies. Problem: But if I restart my system without signing out, the session is still alive. How can I prevent this? from server side. I can try to delete cookies but it is not practical, as each user will have different preferences.

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  • Session locked, Kubuntu 12.10

    - by user101815
    After leaving my laptop for a while, my Kubuntu session closed. (I'm not sure which of the various timeout criteria caused it.) So I got a screen that said my session was locked and I needed to provide my password to unlock it. That's a nuisance, not a big problem, but I'd like to fix it so timed-out sessions don't lock the session. I assume there's something in System Settings to disable the lockout -- but where? I looked in Power Management and found a setting "Lock screen on resume", but it's unchecked. Is this possibly a bug?

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  • How to avoid the "divide by zero" error in SQL?

    - by Henrik Staun Poulsen
    I hate this error message: Msg 8134, Level 16, State 1, Line 1 Divide by zero error encountered. What is the best way to write SQL code, so that I will never see this error message again? I mean, I could add a where clause so that my divisor is never zero. Or I could add a case statement, so that there is a special treatment for zero. Is the best way to use a NullIf clause? Is there better way, or how can this be enforced?

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  • LINQ to SQL vs Entity Framework for an app with a future SQL Azure version

    - by Craig L
    I've got a vertical market Dot Net Framework 1.1 C#/WinForms/SQL Server 2000 application. Currently it uses ADO.Net and Microsoft's SQLHelper for CRUD operations. I've successfully converted it to Dot Net Framework 4 C#/WinForms/ SQL Server 2008. What I'd like to do is also offer my customers the ability to use SQL Azure as a backend storage for their data instead of local/LAN SQL Server. If I know SQL Azure is in my application's future, should I: A. Switch to LINQ to SQL B. Swith to Entity Framework C. Stick with ADO.Net and SQLHelper Thanks !

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  • Sharing ASP.NET State databases between multiple apps

    - by MikeWyatt
    Is it better for a collection of ASP.NET web apps to share the same session database, or should each one have its own? If there is no significant difference, having a single database would be preferable due to easier maintenance. Background My team has an assortment of ASP.NET web apps, all written in either Monorail 1.1 or ASP.NET MVC 1.0. Each app currently uses a dedicated session state database. I'm working on adding a new site to that list, and am debating whether I should create another new session database, or just share an existing one with another app.

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  • Problems with ASP.NET State Service version; state service is 1.1, website is 3.5

    - by Mick Byrne
    Hi there, I have a ASP.NET 3.5 website running on Windows Server 2003 and I'm using the ASP.NET State Service to manage sessions. It will appear to be working then I regularly get an error saying my code needs to have version 2.0 of the State Service running to work (I think that's what it said, I've temporarily switched back to storing sessions InProc). Refresh the page and the error goes away (for a bit, it's bound to come back). So I looked at the properties of the ASP.NET State Service in the Services interface and it's mapping to a .exe in the 1.1 framework folder: C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_state.exe There's a corresponding version in the 2.0 framework folder, but I don't know how to add it as a new service. I'm also not sure that adding the 2.0 version (and stopping and/or removing the 1.1 version) will solve the problem. Thanks in advance for any help anyone can provide. Mick

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  • Zend_Session: unserialize session data

    - by takeshin
    I'm using session SaveHandler to persist session data in the database. Sample session_data column from the database: Messenger|a:1:{s:13:"page_messages";a:0:{}}userSession|a:1:{s:7:"referer";s:32:"http://cms.dev/user/profile/view";}Zend_Auth|a:1:{s:7:"storage";O:19:"User_Model_Identity":3:{s:2:"id";s:1:"1";s:8:"username";s:13:"administrator";s:4:"slug";s:13:"administrator";}} I want to delete Zend_Auth object from this session data. How can I unserialize those objects and remove object I need? I suspect, that I don't have to write my custom parser, that Zend_Session already has a method to do this. I have tried different combinations of unserialize but it still returns false. I'm using autoloader from ZF 1.10.2 and Doctrine 1.2

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  • Changing expiry on ASP.NET's Session State cookie

    - by Charlie Somerville
    I'm using ASP.NET Session State to keep track of logged in users on my site. However, one problem I'm running into is that by default ASP.NET session cookies are set to expire when the browser closes. I've tried setting my own ASP.NET_SessionId cookie and modifying the cookie's expiry using something similar to the following code: Response.Cookies["ASP.NET_SessionId"].Expires = DateTime.Now.AddMonths(1); None of these approaches work, they all set a second cookie with the same name. Is there a way of changing the session cookie's expiry?

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  • Increase php session time via .htaccess not working

    - by Ken
    I want to create the session timeout to 6 hours but my browser is still timing out in 1/2 hour. I am on a PLESK server. I updated .htaccess php_value session.gc_maxlifetime 21600 php_value session.cache_expire 21600 php_value session.cookie_lifetime 21600 Here is the relevant PHPinfo: Local Master session.gc_maxlifetime 21600 1440 session.cache_expire 21600 180 session.gc_maxlifetime 21600 1440

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  • Database Firewall

    - by ???02
    Database Firewall?????SQL????????SQL????????????WEB?????HTTP??????SQL????????SQL????????????????????????????????????????????????????????????SQL??????????????????????????????????????·WEB???????????????????·??????????????????WEB???????????WEB??????????Web?????????????????IPA???????????SQL?????????????????????SQL??????????????????????SQL????????????????WEB??????????????????????????????????????????????????????????????????????????????????????????????WEB????????????????????????????????????????B to B?B to C???WEB????????????????????????????????????????????????????????????????????????????WEB?????????????????????WEB??????????????????·??????????????????????????????????????????????????????????????????????????????????????????WEB???????SQL?????????????????????????????Oracle Database Firewall???SQL??????????????????????????????????????????????????????????????????????????????2011?Oracle Database Firewall?????????·????????????????????????????????????????Oracle Database Firewall??????????????????SQL?????????·?????????????????????? Oracle Database Fireawall ?Oracle Database Firewall???????????????????????????????????????????????????????????SQL??????????????????????????????????????????2????????????????????SQL???Pass?Block????????????SQL?????????????????????????????????????????????????????????????????????????????????SQL????????????????????????????????????????????????????????????????????????????????????????????SQL?Oracle Database Firewall???????????????????SQL????????????????WEB??????????Oracle Database Firewall???????????????????????????????????Oracle Database??????SQL Server?DB2?Sybase??????????2????????Oracle Database Firewall?????????????????????????????????????????????????Oracle Database Firewall?????????????????????????????????????????????SQL???????????????????????????????????????????????????????????SPAN???(?????????)?????????????????????????????????SQL???????????????????????????????????????????SQL?Block???Pass??????????????????????????????????IDS?IPS????????????????????WAF (Web Application Firewall)? ??????????????????????????????????Database Firewall???????????????SQL????????????SQL????400????????????????(ISO/IEC 9075)??????????Oracle Database Firewall???????????????????????????????????????????SQL?????????????????????SQL??????Oracle Database Firewall??Oracle Database, SQL Server, DB2??????????????????????SQL???????????????????SQL??????????????????????????????????SQL???????????????????????????????????SQL????????????????????????????????????Oracle Database Firewall???SQL??????Oracle Database Firewall?????????????????????????????????????????????????????????????????????????????(Oracle Database???10gR2??XML??????????????????????????????????????????????????????????????Oracle Database???????????????????Oracle Database???????????????????????????????)???Oracle Database Firewall??????????????????????????????????????????????????????????????Oracle Database Firewall????????????????????????????????????????????????????????? ?????? Oracle Direct

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  • Whether to use UNION or OR in SQL Server Queries

    - by Dinesh Asanka
    Recently I came across with an article on DB2 about using Union instead of OR. So I thought of carrying out a research on SQL Server on what scenarios UNION is optimal in and which scenarios OR would be best. I will analyze this with a few scenarios using samples taken  from the AdventureWorks database Sales.SalesOrderDetail table. Scenario 1: Selecting all columns So we are going to select all columns and you have a non-clustered index on the ProductID column. --Query 1 : OR SELECT * FROM Sales.SalesOrderDetail WHERE ProductID = 714 OR ProductID =709 OR ProductID =998 OR ProductID =875 OR ProductID =976 OR ProductID =874 --Query 2 : UNION SELECT * FROM Sales.SalesOrderDetail WHERE ProductID = 714 UNION SELECT * FROM Sales.SalesOrderDetail WHERE ProductID = 709 UNION SELECT * FROM Sales.SalesOrderDetail WHERE ProductID = 998 UNION SELECT * FROM Sales.SalesOrderDetail WHERE ProductID = 875 UNION SELECT * FROM Sales.SalesOrderDetail WHERE ProductID = 976 UNION SELECT * FROM Sales.SalesOrderDetail WHERE ProductID = 874 So query 1 is using OR and the later is using UNION. Let us analyze the execution plans for these queries. Query 1 Query 2 As expected Query 1 will use Clustered Index Scan but Query 2, uses all sorts of things. In this case, since it is using multiple CPUs you might have CX_PACKET waits as well. Let’s look at the profiler results for these two queries: CPU Reads Duration Row Counts OR 78 1252 389 3854 UNION 250 7495 660 3854 You can see from the above table the UNION query is not performing well as the  OR query though both are retuning same no of rows (3854).These results indicate that, for the above scenario UNION should be used. Scenario 2: Non-Clustered and Clustered Index Columns only --Query 1 : OR SELECT ProductID,SalesOrderID, SalesOrderDetailID FROM Sales.SalesOrderDetail WHERE ProductID = 714 OR ProductID =709 OR ProductID =998 OR ProductID =875 OR ProductID =976 OR ProductID =874 GO --Query 2 : UNION SELECT ProductID,SalesOrderID, SalesOrderDetailID FROM Sales.SalesOrderDetail WHERE ProductID = 714 UNION SELECT ProductID,SalesOrderID, SalesOrderDetailID FROM Sales.SalesOrderDetail WHERE ProductID = 709 UNION SELECT ProductID,SalesOrderID, SalesOrderDetailID FROM Sales.SalesOrderDetail WHERE ProductID = 998 UNION SELECT ProductID,SalesOrderID, SalesOrderDetailID FROM Sales.SalesOrderDetail WHERE ProductID = 875 UNION SELECT ProductID,SalesOrderID, SalesOrderDetailID FROM Sales.SalesOrderDetail WHERE ProductID = 976 UNION SELECT ProductID,SalesOrderID, SalesOrderDetailID FROM Sales.SalesOrderDetail WHERE ProductID = 874 GO So this time, we will be selecting only index columns, which means these queries will avoid a data page lookup. As in the previous case we will analyze the execution plans: Query 1 Query 2 Again, Query 2 is more complex than Query 1. Let us look at the profile analysis: CPU Reads Duration Row Counts OR 0 24 208 3854 UNION 0 38 193 3854 In this analyzis, there is only slight difference between OR and UNION. Scenario 3: Selecting all columns for different fields Up to now, we were using only one column (ProductID) in the where clause.  What if we have two columns for where clauses and let us assume both are covered by non-clustered indexes? --Query 1 : OR SELECT * FROM Sales.SalesOrderDetail WHERE ProductID = 714 OR CarrierTrackingNumber LIKE 'D0B8%' --Query 2 : UNION SELECT * FROM Sales.SalesOrderDetail WHERE ProductID = 714 UNION SELECT * FROM Sales.SalesOrderDetail WHERE CarrierTrackingNumber  LIKE 'D0B8%' Query 1 Query 2: As we can see, the query plan for the second query has improved. Let us see the profiler results. CPU Reads Duration Row Counts OR 47 1278 443 1228 UNION 31 1334 400 1228 So in this case too, there is little difference between OR and UNION. Scenario 4: Selecting Clustered index columns for different fields Now let us go only with clustered indexes: --Query 1 : OR SELECT * FROM Sales.SalesOrderDetail WHERE ProductID = 714 OR CarrierTrackingNumber LIKE 'D0B8%' --Query 2 : UNION SELECT * FROM Sales.SalesOrderDetail WHERE ProductID = 714 UNION SELECT * FROM Sales.SalesOrderDetail WHERE CarrierTrackingNumber  LIKE 'D0B8%' Query 1 Query 2 Now both execution plans are almost identical except is an additional Stream Aggregate is used in the first query. This means UNION has advantage over OR in this scenario. Let us see profiler results for these queries again. CPU Reads Duration Row Counts OR 0 319 366 1228 UNION 0 50 193 1228 Now see the differences, in this scenario UNION has somewhat of an advantage over OR. Conclusion Using UNION or OR depends on the scenario you are faced with. So you need to do your analyzing before selecting the appropriate method. Also, above the four scenarios are not all an exhaustive list of scenarios, I selected those for the broad description purposes only.

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