[转]SQL SERVER整理索引碎片测试

> 5% 且 < = 30%

ALTER INDEX REORGANIZE

> 30%

ALTER INDEX REBUILD WITH (ONLINE = ON)*

/**************************************
作用:在线整理索引碎片
时间:2008-5-15
说明：
          根据微软的示例改编
          适用于无法停机重建索引的情况，
          在线整理索引碎片，并更新表的统计信息以增强效果。
          另外可以自定义需要整理的索引的逻辑碎片程度，扫描密度，页数
          必须要在数据库访问较少的时候执行 
***************************************/
CREATE PROC [dbo].[SYS_IndexDrag]
AS
BEGIN

SET NOCOUNT ON
DECLARE @tablename VARCHAR (128)
DECLARE @execstr VARCHAR (255)
DECLARE @objectid INT
DECLARE @indexid INT
DECLARE @frag DECIMAL
DECLARE @maxfrag DECIMAL--逻辑碎片

DECLARE @MaxScanDensity DECIMAL--扫描密度

DECLARE @Page INT --8k页数,设定一个限度对一定大的索引进行整理

DECLARE @TmpName VARCHAR(150)

-- Decide on the maximum fragmentation to allow

SELECT @maxfrag = 30.0
SELECT @MaxScanDensity=70.0
SELECT @Page=400

-- Declare cursor

DECLARE tables CURSOR FOR
   SELECT 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 cursor for list of indexes to be defragged

DECLARE indexes CURSOR FOR
   SELECT ObjectName, ObjectId, IndexId, LogicalFrag
   FROM #fraglist
   WHERE (LogicalFrag >= @maxfrag OR [ScanDensity]<=@MaxScanDensity) AND [CountPages]>=@page
      AND INDEXPROPERTY (ObjectId, IndexName, ‘IndexDepth‘) > 0

-- Open the cursor

OPEN indexes

-- loop through the indexes

FETCH NEXT
   FROM indexes
   INTO @tablename, @objectid, @indexid, @frag

WHILE @@FETCH_STATUS = 0
BEGIN
  
   --在线整理碎片

  
   PRINT ‘Executing DBCC INDEXDEFRAG (0, ‘ + RTRIM(@tablename) + ‘,
      ‘ + RTRIM(@indexid) + ‘) - fragmentation currently ‘
       + RTRIM(CONVERT(varchar(15),@frag)) + ‘%‘
   SELECT @execstr = ‘DBCC INDEXDEFRAG (0, ‘ + RTRIM(@objectid) + ‘,
       ‘ + RTRIM(@indexid) + ‘)‘
   EXEC (@execstr)
  
   --更新统计信息

  
   IF @TmpName<>@tablename
   BEGIN
        SET @tmpName=@tableName
        EXEC(‘UPDATE STATISTICS ‘+@TableName) 
   END
    
   FETCH NEXT
      FROM indexes
      INTO @tablename, @objectid, @indexid, @frag
END

-- Close and deallocate the cursor

CLOSE indexes
DEALLOCATE indexes

-- Delete the temporary table

DROP TABLE #fraglist


END

GO