• sqlserver2008 如何定时清理索引碎片


    sqlserver2008 如何定时清理索引碎片

    查询索引引起的表垃圾碎片sql脚本:

     SELECT object_name(a.object_id) [TableName] ,a.index_id ,name [IndexName] ,avg_fragmentation_in_percent 
    From sys.dm_db_index_physical_stats ( DB_ID() , NULL , NULL, NULL, NULL ) 
    As a JOIN sys.indexes AS b ON a.object_id = b.object_id AND a.index_id = b.index_id
    Where avg_fragmentation_in_percent > 0
    Order By avg_fragmentation_in_percent Desc 


    ------解决方案--------------------

    维护计划,其中有一项是索引重整.

    全界面操作.


    ------解决方案--------------------
    declare @Db_name nvarchar(256)
    ,@SchemaName nvarchar(256)
    ,@TableName Nvarchar(256)
    ,@IndexName Nvarchar(512)
    ,@PctFrag decimal
    ,@Defrag nvarchar(max)

    declare frg_cur cursor for
    select d.name,e.name,c.name ,b.name ,a.avg_fragmentation_in_percent  
    from sys.dm_db_index_physical_stats(DB_ID(''),NULL,NULL,NULL,'SAMPLED') as a
    join sys.indexes as b on a.object_id=b.object_id and a.index_id=b.index_id  
    join sys.tables as c on a.object_id=c.object_id  
    join sys.databases as d on a.database_id=d.database_id
    join sys.schemas as e on c.schema_id=e.schema_id
    where a.avg_fragmentation_in_percent >20--索引碎片的大小百分比
    and c.type='U' and a.page_count>8

    open frg_cur
    fetch next from frg_cur into @Db_name,@SchemaName,@TableName,@IndexName,@PctFrag
    while @@FETCH_STATUS=0
    begin
    if @PctFrag between 20.0 and 40.0
    begin
    set @Defrag=N' ALTER INDEX '+@IndexName+' ON '+@Db_name+'.'+@SchemaName+'.'+ @TableName +' REORGANIZE'--重新组织索引页不删除索引
    EXEC SP_EXECUTESQL @Defrag

    end
    else if @PctFrag>40.0
    begin
    SET @Defrag=N' ALTER INDEX '+@IndexName+' ON '+@Db_name+'.'+@SchemaName+'.'+ @TableName +' REBUILD ONLINE=ON'--联机重建索引。即不锁定表重新创建索引
    EXEC SP_EXECUTESQL @Defrag

    end
    fetch next from frg_cur into @Db_name,@SchemaName,@TableName,@IndexName,@PctFrag
    end
    close frg_cur
    deallocate frg_cur
    ---记得把系统数据库过滤掉就可以了

    写个作业 调用 
    ------解决方案--------------------
    ----将其放到作业中定时执行即可(最好在生产服务器空闲的时候执行)。仅供参考。

     

    create procedure pr_auto_indexdefrag
    as
    set nocount on

    begin

     declare @Db_name nvarchar(256)
    ,@SchemaName nvarchar(256)
    ,@TableName Nvarchar(256)
    ,@IndexName Nvarchar(512)
    ,@PctFrag decimal
    ,@Defrag nvarchar(max)

     

    if exists(select 1 from sys.objects where object_id =object_id(N'#tmp')) Drop table #tmp;
    create table #tmp(dbname nvarchar(256),tablename nvarchar(256),indexname nvarchar(256),schemaname nvarchar(256),avgfragment decimal)

    exec sp_MSforeachdb 'insert into #tmp(dbname,tablename,indexname,schemaname,avgfragment)
    select ''?'' dbname,c.name,b.name,e.name,a.avg_fragmentation_in_percent  
    from ?.sys.dm_db_index_physical_stats(DB_ID(''?''),NULL,NULL,NULL,''SAMPLED'') as a
    join ?.sys.indexes as b on a.object_id=b.object_id and a.index_id=b.index_id  
    join ?.sys.tables as c on a.object_id=c.object_id  
    join sys.databases as d on a.database_id=d.database_id
    join ?.sys.schemas as e on c.schema_id=e.schema_id
    where a.avg_fragmentation_in_percent >20
    and c.type=''U'' and a.page_count>8
    and d.name like ''caihong_%'''

     declare frg_cur cursor for
    select * from #tmp


    open frg_cur
    fetch next from frg_cur into @Db_name,@TableName,@IndexName,@SchemaName,@PctFrag
    while @@FETCH_STATUS=0
    begin

    if @PctFrag between 20.0 and 40.0
    begin
    set @Defrag=N' ALTER INDEX '+@IndexName+' ON'+@Db_name+'.'+@SchemaName+'.'+ @TableName +' REORGANIZE'--重新组织索引页不删除索引
    EXEC SP_EXECUTESQL @Defrag
    end
    else if @PctFrag>40.0
    begin
    SET @Defrag=N' ALTER INDEX '+@IndexName+' ON'+@Db_name+'.'+@SchemaName+'.'+ @TableName +' REBUILD WITH (ONLINE = ON )'--联机重建索引。即不锁定表重新创建索引
    EXEC SP_EXECUTESQL @Defrag
    end
    fetch next from frg_cur into @Db_name,@TableName,@IndexName,@SchemaName,@PctFrag
    end
    close frg_cur
    deallocate frg_curend

    end

    set nocount off

    ------解决方案--------------------
    mark一下
    尽量争取在生产环境空闲的情况 下优化
    重整索引很耗资源的 
    ------解决方案--------------------

    探讨
    ----将其放到作业中定时执行即可(最好在生产服务器空闲的时候执行)。仅供参考。



    create procedure pr_auto_indexdefrag
    as
    set nocount on

    begin

    declare @Db_name nvarchar(256)
    ,@SchemaName nvarchar(256)
    ,@TableName Nvarc……


    ------解决方案--------------------
    作业或者维护计划都可以实现的。 

    转载:http://www.myexception.cn/sql-server/319573_2.html

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  • 原文地址:https://www.cnblogs.com/Gxiaopan/p/5457360.html
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