Temporary Tables in SQL Server. Temporary tables are just that. They are used most often to provide workspace for the intermediate results when processing data within a batch or procedure. In my previous blog post, I had shared how you can leverage SQL Server Performance Dashboard SSRS Reports for monitoring and point in time troubleshooting for large. In this article we'll show what are the SQL Server Activity Monitor requirements, what panes does it consist of, and explain how to start it. This article describes the most important SQL Server disk performance metrics such as Average Disk sec/Read, Average Disk sec/Write, and more. The #1 SQL Server community and education site, with articles, news, forums, scripts and FAQs.They are also used to pass a table from a table- valued function, to pass table- based data between stored procedures or, more recently in the form of Table- valued parameters, to send whole read- only tables from applications to SQL Server routines, or pass read- only temporary tables as parameters. Once finished with their use, they are discarded automatically. Temporary tables come in different flavours including, amongst others, local temporary tables (starting with #), global temporary tables (starting with ##), persistent temporary tables (prefixed by Temp. DB.), and table variables.(starting with (@)Before we get too deep into the technology, I’d advise that you should use table variables where possible. They’re easy, and SQL Server does the work for you. ![]() They also tend to cause fewer problems to a hard- working OLTP system. Just occasionally, you may need to fine- tune them to get good performance from them in joins, but I’ll explain that in a moment, However, if you are doing more complex processing on temporary data or likely to use more than reasonably small amounts of data in them, then local temporary tables are likely to be a better choice. Table Variables. Table variables are used within the scope of the routine or batch within which they are defined, and were originally created to make table- valued functions possible. However, they are good for many of the uses that the traditional temporary table was put to. They behave like other variables in their scoping rules. Once out of scope, they are disposed of. These are much easier to work with, and pretty secure, and they trigger fewer recompiles in the routines where they’re used than if you were to use temporary tables. Table variables require less locking resources as they are ‘private’ to the process that created them. Transaction rollbacks do not affect them because table variables have limited scope and are not part of the persistent database, so they are handy for creating or storing data that ought to survive roll backs such as log entries. The downside of table variables is that they are often disposed of before you can investigate their contents for debugging, or use them to try out different SQL expressions interactively. If your application is conservative and your data volumes light you’ll never want anything else. However, you can hit problems. One difficulty is that table variables can only be referenced in their local scope, so you cannot process them using dynamic SQL as you might with a temporary table or table- valued parameter. This is because you can’t refer an externally- defined table variable within dynamic SQL that you then execute via the EXEC statement or the sp_Execute. SQL stored procedure because the dynamic SQL is executed outside the scope of the table variable. You can, of course, create, and then use, the table variable inside the dynamic SQL because the table variable would be in scope. However, once the dynamic SQL is run, there would be no table variable There are a few anomalies to be aware of too. You can’t, for example, change the table definition after the initial DECLARE statement. In SQL Server 2. 00. SELECT INTO statement or a INSERT EXEC (now fixed); You can’t call user- defined functions from CHECK constraints, DEFAULT values, and computed columns in the table variable. The only constraints that you’re allowed beyond CHECK constraints are PRIMARY KEY, UNIQUE KEY, and NULL / NOT NULLThe trickiest problems, though, come with increasing size of the tables, because you can’t declare an index explicitly and distribution statistics aren’t maintained on them. The Query Optimiser assumes that there is only one row in the table. You also cannot generate parallel query plans for a SQL expression that is modifying the table’s contents. To partially get around the index restriction, you can use constraints to do the same thing. Most essential is the Primary Key constraint which allows you to impose a clustered index, but unique constraints are useful for performance. The Query optimiser will happily use them if they are around. The biggest problem with table variables is that statistics aren’t maintained on the columns. This means that the query optimiser has to make a guess as to the size and distribution of the data and if it gets it wrong, then you’re going to see poor performance on joins: If this happens, there is little you can do other than to revert to using classic local temporary tables. One thing you can try is to add option (recompile) to the statement that involves the table variable joining with other tables. By doing this, SQL Server will be able to detect number of rows at recompile because the rows will have already been populated. This doesn’t entirely solve the problem since the optimiser still has no distribution statistics and can, usually where the distribution is skewed, produce a bad plan. In this demo, the join was reduced in time by three quarters simply by adding the OPTION (RECOMPILE)1. SETnocount. ONDECLARE@First. Table. TABLE(Random. Integer. INT)DECLARE@Second. Table. TABLE(Random. Integer. INT)DECLARE@When. We. Started. DATETIMEDECLARE@ii. INTBEGINTRANSACTIONSET@ii=0. WHILE@ii< 1. 00. BEGIN INSERT INTO@First. Table VALUES (RAND()*1. SET@ii=@ii+1 ENDSET@ii=0. WHILE@ii< 1. 00. BEGIN INSERT INTO@Second. Table VALUES (RAND()*1. SET@ii=@ii+1 ENDCOMMITTRANSACTIONSELECT @When. We. Started=GETDATE()SETSTATISTICSPROFILEONSELECT COUNT(*)FROM @First. Tablefirst INNERJOIN@Second. Tablesecond ONfirst. Random. Integer=second. Random. Integer. OPTION(RECOMPILE) - - 1. Ms as opposed to 6. Ms without the hint. SETSTATISTICSPROFILEOFFSELECT 'That took ' +CONVERT(VARCHAR(8),DATEDIFF(ms,@When. We. Started,GETDATE())) +' ms'go. Now if you can make what goes into the tables unique, you can then use a primary key constraint on these tables. This allowed the optimiser to use a clustered index seek instead of a table scan and the execution time was too rapid to measure. Start with table variables, but drop back to using local temporary tables if you hit performance problems. Some people are bold enough to give advice in terms of the number of rows in a table, and I’ve seen 1. I’ve seen far larger table variables perform perfectly satisfactorily over time, and far smaller ones give trouble. However, in smaller tables, the trouble is less detectable! Table- Valued Parameters. The Table- Valued Parameter (TVP) is a special type of table variable that extends its use. When table variables are passed as parameters, the table is materialized in the Temp. DB system database as a table variable and passed by reference, a pointer to the table in the Temp. DB. Table- valued parameters have been used since SQL Server 2. Transact- SQL routine or to a batch via sp_Execute. SQL. Their particular value to the programmer is that they can be used within TSQL code as well as in the client application, so they are good for sending client tables to the server. From TSQL, you can declare table- valued variables, insert data into them, and pass these variables as table- valued parameters to stored procedures and functions. Their more general usefulness is limited by the fact that they are only passed as read- only. You can’t do UPDATE, DELETE, or INSERT statements on a table- valued parameter in the body of a routine. You need to create a User- Defined Table Type and define a table structure to use them. Here is a simple example of their use in TSQL1. First you need to create a table type. CREATETYPENames. ASTABLE(Name. VARCHAR(1. 0)); GO/* Next, Create a procedure to receive data for the table- valued parameter, the table of names and select one item from the table*/CREATEPROCEDUREChoose. AName @Candidate. Names. Names. READONLYASDECLARE@candidates. TABLE(NAMEVARCHAR(1. Order. UNIQUEIDENTIFIER)INSERT INTO@candidates (name,theorder) SELECT name,NEWID() FROM @Candidate. Names. SELECTTOP1 NAMEFROM @Candidates. ORDERBYthe. Order. GO/* Declare a variable that references the type for our list of cows. DECLARE@My. Favourite. Cow. Name. ASNames; /* Add data to the table variable. INSERT INTO@My. Favourite. Microsoft SQL Server Version List. Microsoft SQL Server Version List. What version of SQL Server do I have? This unofficial build chart lists all of the known Service Packs (SP), Cumulative Updates (CU), patches, hotfixes and other builds of MS SQL Server 2. R2, 2. 00. 8, 2. 00. Useful articles: Quick summary: All SQLServer service packs are cumulative, meaning that each new service pack contains all the fixes that are included with previous service packs and any new fixes. You can comment here. If you know of a hotfix build or KB that we don't have listed here, please use the comments. Legend: CTPCommunity Technology Preview (beta release)RCRelease Candidate. RTMReleased To Manufacturing; It is the original, released build version of the product, i. DVD or when you download the ISO file from MSDN. CUCumulative Update; Cumulative updates contain the bug fixes and enhancements–up to that point in time–that have been added since the previous Service Pack release and will be contained in the next service pack release. Installation of the Cumulative Update is similar to the installation of a Service Pack. Cumulative Updates are not fully regression tested.* Since January 2. Microsoft recommends ongoing, proactive installation of SQL Server CUs as they become available. SQL Server CUs are certified to the same levels as Service Packs, and should be installed with the same level of confidence. SPService Pack; much larger collection of hotfixes that have been fully regression tested. In some cases delivers product enhancements. GDRGeneral Distribution Release; GDR fixes should not contain any of the CU updates. QFEQuick Fix Engineering; QFE updates include CU fixes. CVECommon Vulnerabilities and Exposures; publicly known information- security vulnerabilities. Microsoft SQL Server 2. Builds. Build. SQLSERVR. EXE Build. File version. QKBKB / Description. Release Date. 14. Microsoft SQL Server 2. Release Candidate 2 (RC2) (Linux support)August 2, 2. Microsoft SQL Server 2. Release Candidate 1 (RC1) (Linux support)July 1. Microsoft SQL Server 2. Community Technical Preview 2. CTP2. 1) (Linux support)May 1. Microsoft SQL Server 2. Community Technical Preview 2. CTP2. 0) (Linux support)April 1. Microsoft SQL Server v. Next Community Technology Preview 1. CTP1. 4) (Linux support)March 1. Microsoft SQL Server v. Next Community Technology Preview 1. CTP1. 3) (Linux support)February 1. Microsoft SQL Server v. Next Community Technology Preview 1. CTP1. 2) (Linux support)January 2. Microsoft SQL Server v. Next Community Technology Preview 1. CTP1. 1) (Linux support)December 1. Microsoft SQL Server v. Next Community Technology Preview 1 (CTP1) (Linux support)November 1. Microsoft SQL Server 2. Builds. Build. SQLSERVR. EXE Build. File version. QKBKB / Description. Release Date. 13. Q4. 04. 07. 14. KB4. Cumulative update 5 (CU5) for SQL Server 2. Service Pack 1 Latest CUSeptember 1. Q4. 02. 43. 05. KB4. Cumulative update 4 (CU4) for SQL Server 2. Service Pack 1 CVE- 2. August 8, 2. 01. 71. Q4. 01. 99. 16. KB4. Cumulative update 3 (CU3) for SQL Server 2. Service Pack 1. May 1. Q4. 01. 31. 06. KB4. Cumulative update 2 (CU2) for SQL Server 2. Service Pack 1. March 2. Q3. 20. 81. 77. KB3. Cumulative update 1 (CU1) for SQL Server 2. Service Pack 1. January 1. Q4. 01. 90. 89. KB4. Security update for SQL Server 2. Service Pack 1 GDR: August 8, 2. CVE- 2. 01. 7- 8. August 8, 2. 01. 7 *new. Q3. 21. 00. 89. KB3. GDR update package for SQL Server 2. SP1. December 1. 6, 2. Q3. 20. 75. 12. KB3. Important update for SQL Server 2. SP1 Reporting Services. November 2. 3, 2. Microsoft SQL Server 2. Service Pack 1 (SP1) Latest SPNovember 1. Q4. 04. 07. 13. KB4. Cumulative update 8 (CU8) for SQL Server 2. September 1. 8, 2. Q4. 02. 43. 04. KB4. Cumulative update 7 (CU7) for SQL Server 2. CVE- 2. 01. 7- 8. August 8, 2. 01. 71. Q4. 01. 99. 14. KB4. Cumulative update 6 (CU6) for SQL Server 2. May 1. 5, 2. 01. 71. Q4. 01. 31. 05. KB4. Cumulative update 5 (CU5) for SQL Server 2. March 2. 1, 2. 01. Q3. 20. 50. 52. KB3. Cumulative update 4 (CU4) for SQL Server 2. January 1. 8, 2. 01. Q3. 21. 01. 10. KB3. On- demand hotfix update package for SQL Server 2. CU3. December 1. 6, 2. Q3. 20. 54. 13. KB3. Cumulative update 3 (CU3) for SQL Server 2. November 8, 2. 01. Q3. 19. 47. 17. KB3. MS1. 6- 1. 36: Description of the security update for SQL Server 2. CU: November 8, 2. November 8, 2. 01. Q3. 19. 91. 71. KB3. On- demand hotfix update package for SQL Server 2. CU2. November 1, 2. Q3. 19. 58. 13. KB3. On- demand hotfix update package for SQL Server 2. CU2. October 2. 6, 2. Q3. 18. 22. 70. KB3. Cumulative update 2 (CU2) for SQL Server 2. September 2. 2, 2. Q3. 16. 46. 74. KB3. Cumulative update 1 (CU1) for SQL Server 2. July 2. 6, 2. 01. Q4. 01. 90. 88. KB4. Security update for SQL Server 2. RTM GDR: August 8, 2. CVE- 2. 01. 7- 8. August 8, 2. 01. 7 *new. Q3. 21. 01. 11. KB3. GDR update package for SQL Server 2. RTMDecember 1. 6, 2. Q3. 19. 47. 16. KB3. MS1. 6- 1. 36: Description of the security update for SQL Server 2. GDR: November 8, 2. November 8, 2. 01. Q3. 17. 92. 58. KB3. Processing a partition causes data loss on other partitions after the database is restored in SQL Server 2. August 1. 7, 2. 01. Q3. 16. 43. 98. KB3. Critical update for SQL Server 2. MSVCRT prerequisites. June 3, 2. 01. 61. Microsoft SQL Server 2. RTM RTMJune 1, 2. Microsoft SQL Server 2. Release Candidate 3 (RC3)April 1. Microsoft SQL Server 2. Release Candidate 2 (RC2)April 1, 2. Microsoft SQL Server 2. Release Candidate 1 (RC1)March 1. Microsoft SQL Server 2. Release Candidate 0 (RC0)March 7, 2. Microsoft SQL Server 2. Community Technology Preview 3. CTP3. 3)February 3, 2. Microsoft SQL Server 2. Community Technology Preview 3. CTP3. 2)December 1. Microsoft SQL Server 2. Community Technology Preview 3. CTP3. 1)November 3. Microsoft SQL Server 2. Community Technology Preview 3. CTP3. 0)October 2. Microsoft SQL Server 2. Community Technology Preview 2. CTP2. 4)September 3. Microsoft SQL Server 2. Community Technology Preview 2. CTP2. 3)August 2. Microsoft SQL Server 2. Community Technology Preview 2. CTP2. 2)July 2. 3, 2. Microsoft SQL Server 2. Community Technology Preview 2. CTP2. 2) [withdrawn]July 2. Microsoft SQL Server 2. Community Technology Preview 2. CTP2. 1)June 2. 4, 2. Microsoft SQL Server 2. Community Technology Preview 2 (CTP2)May 2. Microsoft SQL Server 2. Builds. Build. SQLSERVR. EXE Build. File version. QKBKB / Description. Release Date. 12. Q4. 03. 25. 41. KB4. Cumulative update package 7 (CU7) for SQL Server 2. Service Pack 2 Latest CUAugust 2. Q4. 01. 90. 94. KB4. Cumulative update package 6 (CU6) for SQL Server 2. Service Pack 2. August 8, 2. Q4. 01. 30. 98. KB4. Cumulative update package 5 (CU5) for SQL Server 2. Service Pack 2. April 1. Q4. 01. 03. 94. KB4. Cumulative update package 4 (CU4) for SQL Server 2. Service Pack 2. February 2. Q3. 20. 43. 88. KB3. Cumulative update package 3 (CU3) for SQL Server 2. Service Pack 2. December 2. Q3. 19. 47. 18. KB3. MS1. 6- 1. 36: Description of the security update for SQL Server 2. Service Pack 2 CU: November 8, 2. November 8, 2. 01. Q3. 18. 87. 78. KB3. Cumulative update package 2 (CU2) for SQL Server 2. Service Pack 2. October 1. Q3. 17. 89. 25. KB3. Cumulative update package 1 (CU1) for SQL Server 2. Service Pack 2. August 2. Q4. 01. 90. 93. KB4. Security update for SQL Server 2. Service Pack 2 GDR: August 8, 2. August 8, 2. 01. 7 *new. Q3. 19. 47. 14. KB3. MS1. 6- 1. 36: Description of the security update for SQL Server 2. Service Pack 2 GDR: November 8, 2. November 8, 2. 01. SQL Server 2. 01. Service Pack 2 (SP2) Latest SPJuly 1. Q4. 01. 90. 99. KB4. Cumulative update package 1. CU1. 3) for SQL Server 2. Service Pack 1. August 8, 2. Q4. 01. 77. 93. KB4. Cumulative update package 1. CU1. 2) for SQL Server 2. Service Pack 1. April 1. Q4. 01. 03. 92. KB4. Cumulative update package 1. CU1. 1) for SQL Server 2. Service Pack 1. February 2. Q3. 20. 43. 99. KB3. Cumulative update package 1. CU1. 0) for SQL Server 2. Service Pack 1. December 2. Q3. 19. 47. 22. KB3. MS1. 6- 1. 36: Description of the security update for SQL Server 2. Service Pack 1 CU: November 8, 2. November 8, 2. 01. Q3. 18. 69. 64. KB3. Cumulative update package 9 (CU9) for SQL Server 2. Service Pack 1. October 1. Q3. 17. 40. 38. KB3. Cumulative update package 8 (CU8) for SQL Server 2. Service Pack 1. August 1. Q3. 17. 43. 70. KB3. A memory leak occurs when you use Azure Storage in SQL Server 2. August 4, 2. 01. 61. Q3. 16. 26. 59. KB3. Cumulative update package 7 (CU7) for SQL Server 2. Service Pack 1. June 2. Q3. 16. 73. 92. KB3. REFRESHED Cumulative update package 6 (CU6) for SQL Server 2. Service Pack 1. May 3. Q3. 14. 45. 24. KB3.
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