sql tuning advisor

threads.Of course, here are a few thread operations can set their own, the maximum recommended for the current system configuration of the logical core number, of course, the large set can be just useless.Second , index Hint hints (index Hint)The so-called index hint hint is to force the query optimizer to perform a scan of a query statement or use a specified index.In this way, we often use in the tuning of a way, many times we create the index is i

, if a field has an index and a field is not indexed, it will cause the engine to discard using the index for a full table scan, such as:Select ID from t where num= or Name = ' admin 'You can query this:Select ID from t where Name = ' admin '5. In and not are also used with caution, otherwise it will cause a full table scan, such as:Select ID from t where num in (1,2,3)For consecutive values, you can use between instead of in:1 3A lot of times it's a good choice to replace in with exists:Select

There should be different filegroups in the database before the partition table is created;Assuming the database name is Df17datapro, create the user table UserID, put the first 500,000 data in the primary filegroup, place the 50~100 in the FG1 filegroup, and put more than 100 in the FG2 filegroup1. Add File group Fg1,fg2ALTER DATABASE Df17datapro ADD FILEGROUP FG1ALTER DATABASE df17dataproadd FILEGROUP fg22. Adding files to a filegroupALTER TABLEDf17dataproADD FILE(NAME=Df17datapro1,filename=

--windows Machine NameSysprep.exe check general, and turn off the machine--Instance NameSELECT @ @SERVERNAME, serverproperty (' SERVERNAME ')If SERVERPROPERTY (' servername ') Begindeclare @server sysnameSet @server = @ @servernameexec sp_dropserver @server = @serverSet @server = Cast (serverproperty (' servername ') as sysname)exec sp_addserver @server = @server, @local = ' local 'EndSELECT @ @SERVERNAME, serverproperty (' SERVERNAME ')VM environment, rapid replication of multiple

in each record to go to B scan again, actually swept the number of rows equal to a result set row x B result set row number. So if the two result sets are large, the result of the join IS bad.SQL Server 2005 Added merge Join, if the Join field of table A and table B is exactly the field of the clustered index, then the order of the table is lined up, as long as the two sides of the row, the cost of this Join is equal to the result set row of a table plus the result set row number of B table, on

. server.2005. Technical Insider "series Conclusion This article first to this bar, the article is short, easy to understand, follow-up on the parallel operation of a part of the content, follow-up articles, this article mainly introduces the parallel operators in the query plan, next we will add some of the SQL Server parallel operations, Then analysis of our daily write additions and deletions to these operators to optimize the items, interest

Label:ObjectiveIn the previous article, we analyzed how the query optimizer works, including: detailed operation steps of the query optimizer, analysis of filter conditions, optimization of index items, and other information.In this article we analyze the detection of several key indicator values in the course of our operation.These indicator values are analyzed to analyze the operation of the statement and to analyze how it is optimized.Through this article we can learn the

Read Catalogue Objective Technical preparation ObjectiveIn the previous article, we analyzed how the query optimizer works, including: detailed operation steps of the query optimizer, analysis of filter conditions, optimization of index items, and other information.In this article we analyze the detection of several key indicator values in the course of our operation.These indicator values are analyzed to analyze the operation of the statement and to analyze how it is optimized

Transferred from: http://www.cnblogs.com/MR_ke/archive/2010/08/25/1807856.htmlSQL 2005 Performance TuningSQL Server runs for a period of time, and as data accumulates, SQL runs less efficiently, and in order to use business system normal actions, IT departments often need to spend a high price on SQL tuning experts to solve. In fact,

Tags: instance default help input extern data package MSDN One fixOriginal: SQL Server performance Tuning resource waiting network I/OI. OverviewThe main wait for network I/O is async_network_io, when SQL Server returns a data result set to the client, the result set is populated into the output cache (ouput cache), and the network layer begins to package the dat

used to find rows in the table Keys: Index used by actual execution plan Key_len: Index length to use Ref: Shows which column or constant is used together with key to select rows from the table. Rows: Displays the number of rows that MySQL needs to check for execution queries. Extra: This column contains important information to resolve the query , very important ! Show index from TableNameThis command helps us to check the index of the table and is the basis for all q

SQL Server Performance Tuning entry (graphic version) Step 1: capture sample data during business peaks(About 2 hours ). The tool used is the profiler that comes with sqlserver, also known as the event probe. For example, after entering, click the button on the leftmost side to create a new trail: DBO permission is required for logon, therefore, you can log on with SA or use Windows integrated verification

add data to the table (delete, update operations, and so on), add the address of the new record to the index, which slows down the new data. Presumably, to be able to read it, it's not exactly right. Knowing the index, we can add the appropriate index above the table to improve the performance of the query statement.You can look at an index as a unique table, SQL query, if the field is indexed field will be indexed to query, then the index of this un

, one is not perfect function also dare to take Out (2000) The second functional architecture of the outstanding design makes the function has a strong continuity and Scalability (2005 2000 of the function to retain and improve). The optimization tool is simple to use 1: Use SQL Server Porfiler (Event Viewer) to record all the steps of the operation database in the business system and save it as a working file. 2: Open sql2005 's database Engine

poorly run applications outweigh the investment in human, program, and technology using reliable load testing methods. Therefore, I would like to provide the following list of load tests for your application, which will be a magic bullet to prevent your SQL Server performance tuning problem. Checklist: Load test--sql server performance

1. New tuning Set Object ***************************************** ---Authorize grant administer any SQL TUNING SET to Scott;---Delete the existing stsbegin Dbms_sqltune. Drop_sqlset (sqlset_name = ' ocpyang_sts '); end;/---new Stsbegin dbms_sqltune. Create_sqlset (sqlset_name = ' ocpyang_sts ', Sqlset_owner = ' SCOTT ', description = ' ocpyangtest '); end;/---Vi

In the DB2 tuning process, you often want to be able to get SQL that is slow to execute in your current production environment, which you can then fine tune for specific slow SQL. The following scripts can be exploited, or are cumbersome to operate, and need to be run manually.DB2 Connect to Tablename;db2-x "Select Current Timestamp | | ' | ' | | Stmt_text | | '

);} /// ///generate time information from the GUID returned by SQL SERVER/// /// comb that contain time information/// Time Public Staticdatetime getdatefromcomb (System.Guid Guid) {datetime basedate=NewDateTime (1900,1,1); byte[] Daysarray =New byte[4]; byte[] Msecsarray =New byte[4]; byte[] Guidarray =GUID. Tobytearray (); //Copy The date parts of the GUID to the respective byte arrays.Array.copy (Guidarray, Guidarray.length-6, Daysarray,2,2);

Recently, the following project encountered an urgent problem, my old horse and young people to fight together. The problem is that many queries are incredibly slow when the pressure data is poured into the database. Said there must be some basic guidelines for performance issues. The order of performance problems tunning 1 Architecture design (software architecture and database design, poor design is almost fatal) 2 Code defects (90% of performance problems) 3 Add index (this is to be deter

execution plan you can see that the performance improvement is still very large. This is the data of the test environment, if the data volume is large, the advantage is more obvious.So for this problem, the cause is that there is a job data processing frequency is relatively high, in the test environment is difficult to locate where there is a problem, and the speed can also be accepted, but in the production environment is always slower, in fact, there is still a reason, only through a variety