zoukankan      html  css  js  c++  java
  • SQL Server 索引维护sql语句

    使用以下脚本查看数据库索引碎片的大小情况: 

    复制代码代码如下:

    DBCC SHOWCONTIG WITH FAST, TABLERESULTS, ALL_INDEXES, NO_INFOMSGS 


    以下使用脚本来处理维护作业: 

    复制代码代码如下:

    /*Perform a 'USE <database name>' to select the database in which to run the script.*/ 
    -- Declare variables 
    SET NOCOUNT ON; 
    DECLARE @tablename varchar(255); 
    DECLARE @execstr varchar(400); 
    DECLARE @objectid int; 
    Declare @IndexName varchar(500); 
    DECLARE @indexid int; 
    DECLARE @frag decimal; 
    DECLARE @maxfrag decimal; 
    DECLARE @TmpName varchar(500); 

    -- Declare @TmpName ='' 
    set @TmpName = '' 

    -- Decide on the maximum fragmentation to allow for. 
    SELECT @maxfrag = 30.0; 

    -- Declare a cursor. 
    DECLARE tables CURSOR FOR 
    SELECT TABLE_SCHEMA + '.' + TABLE_NAME 
    FROM INFORMATION_SCHEMA.TABLES 
    WHERE TABLE_TYPE = 'BASE TABLE'; 

    -- Create the table. 
    CREATE TABLE #fraglist ( 
    ObjectName char(255), 
    ObjectId int, 
    IndexName char(255), 
    IndexId int, 
    Lvl int, 
    CountPages int, 
    CountRows int, 
    MinRecSize int, 
    MaxRecSize int, 
    AvgRecSize int, 
    ForRecCount int, 
    Extents int, 
    ExtentSwitches int, 
    AvgFreeBytes int, 
    AvgPageDensity int, 
    ScanDensity decimal, 
    BestCount int, 
    ActualCount int, 
    LogicalFrag decimal, 
    ExtentFrag decimal); 

    -- Open the cursor. 
    OPEN tables; 

    -- Loop through all the tables in the database. 
    FETCH NEXT 
    FROM tables 
    INTO @tablename; 

    WHILE @@FETCH_STATUS = 0 
    BEGIN; 
    -- Do the showcontig of all indexes of the table 
    INSERT INTO #fraglist 
    EXEC ('DBCC SHOWCONTIG (''' + @tablename + ''') 
    WITH FAST, TABLERESULTS, ALL_INDEXES, NO_INFOMSGS'); 
    FETCH NEXT 
    FROM tables 
    INTO @tablename; 
    END; 

    -- Close and deallocate the cursor. 
    CLOSE tables; 
    DEALLOCATE tables; 

    -- Declare the cursor for the list of indexes to be defragged. 
    DECLARE indexes CURSOR FOR 
    SELECT ObjectName, ObjectId,IndexName,IndexId, LogicalFrag 
    FROM #fraglist 
    WHERE INDEXPROPERTY (ObjectId, IndexName, 'IndexDepth') > 0; 

    -- Open the cursor. 
    OPEN indexes; 

    -- Loop through the indexes. 
    FETCH NEXT 
    FROM indexes 
    INTO @tablename, @objectid, @IndexName,@indexid, @frag; 


    WHILE @@FETCH_STATUS = 0 
    BEGIN; 
    if @frag < @maxfrag 
    Begin 
    SELECT @execstr = 'ALTER INDEX [' + RTRIM(@IndexName) + '] ON [' + RTRIM(@tablename) + '] REORGANIZE WITH ( LOB_COMPACTION = ON ) ' 
    print @maxfrag + ' ' + @execstr 
    End 
    else 
    Begin 
    SELECT @execstr = 'ALTER INDEX [' + RTRIM(@IndexName) + '] ON [' + RTRIM(@tablename) + '] REBUILD WITH ( PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON, SORT_IN_TEMPDB = OFF, ONLINE = OFF )' 
    print @maxfrag + ' ' + @execstr 
    End 

    EXEC (@execstr); 

    --更新统计信息 
    IF @TmpName<>@tablename 
    BEGIN 
    SET @tmpName=@tableName 
    PRINT 'UPDATE STATISTICS '+@TableName + ' WITH FULLSCAN ' 
    EXEC ('UPDATE STATISTICS '+@TableName + ' WITH FULLSCAN ') 
    END 


    FETCH NEXT 
    FROM indexes 
    INTO @tablename, @objectid, @IndexName,@indexid, @frag; 
    END; 

    -- Close and deallocate the cursor. 
    CLOSE indexes; 
    DEALLOCATE indexes; 

    -- Delete the temporary table. 
    DROP TABLE #fraglist; 
    GO 
  • 相关阅读:
    进程池和线程池
    GIL和互斥锁
    GIL全局解释器锁
    线程锁
    关于迭代器的一些总结
    python在linux上的GUI无法弹出界面
    import Tkinter的时候报错
    检查字符串中的结束标记
    关于模块的使用
    python中pip的安装
  • 原文地址:https://www.cnblogs.com/zcm123/p/3828834.html
Copyright © 2011-2022 走看看