SQL数据库的索引维护指导(3)_SQL SERVER数据库_黑客防线网安服务器维护基地--Powered by WWW.RONGSEN.COM.CN

SQL数据库的索引维护指导(3)

作者:黑客防线网安SQL维护基地 来源:黑客防线网安SQL维护基地 浏览次数:0

本篇关键词:指导维护索引数据库
黑客防线网安网讯:  针对SQL Server 2000的脱机维护:  sp_msforeachtable @command1="dbcc dbreindex('?','',85)"  针对SQL Server 2005的通用维护过程   (碎片小于30%的联机组织,...

  针对SQL Server 2000的脱机维护:

  sp_msforeachtable @command1="dbcc dbreindex('?','',85)"
  针对SQL Server 2005的通用维护过程
  (碎片小于30%的联机组织碎片>=30%的脱机重建):

-- ensure a USE <databasename> statement has been executed first.
SET NOCOUNT ON;
DECLARE @objectid int;
DECLARE @indexid int;
DECLARE @partitioncount bigint;
DECLARE @schemaname sysname;
DECLARE @objectname sysname;
DECLARE @indexname sysname;
DECLARE @partitionnum bigint;
DECLARE @partitions bigint;
DECLARE @frag float;
DECLARE @command varchar(8000);
-- ensure the temporary table does not exist
IF EXISTS (SELECT name FROM sys.objects WHERE name = 'work_to_do')
    DROP TABLE work_to_do;
-- conditionally select from the function, converting object and index IDs to names.
SELECT
    object_id AS objectid,
    index_id AS indexid,
    partition_number AS partitionnum,
    avg_fragmentation_in_percent AS frag
INTO work_to_do
FROM sys.dm_db_index_physical_stats (DB_ID(), NULL, NULL , NULL, 'LIMITED')
WHERE avg_fragmentation_in_percent > 10.0 AND index_id > 0;
-- Declare the cursor for the list of partitions to be processed.
DECLARE partitions CURSOR FOR SELECT * FROM work_to_do;
-- Open the cursor.
OPEN partitions;

-- Loop through the partitions.
FETCH NEXT
   FROM partitions
   INTO @objectid, @indexid, @partitionnum, @frag;

WHILE @@FETCH_STATUS = 0
    BEGIN;
        SELECT @objectname = o.name, @schemaname = s.name
        FROM sys.objects AS o
        JOIN sys.schemas as s ON s.schema_id = o.schema_id
        WHERE o.object_id = @objectid;

        SELECT @indexname = name
        FROM sys.indexes
        WHERE  object_id = @objectid AND index_id = @indexid;

        SELECT @partitioncount = count (*)
        FROM sys.partitions
        WHERE object_id = @objectid AND index_id = @indexid;

-- 30 is an arbitrary decision point at which to switch between reorganizing and rebuilding
IF @frag < 30.0 and @frag>5
    BEGIN;
    SELECT @command = 'ALTER INDEX ' + @indexname + ' ON ' + @schemaname + '.' + @objectname + ' REORGANIZE';
    IF @partitioncount > 1
        SELECT @command = @command + ' PARTITION=' + CONVERT (CHAR, @partitionnum);
    EXEC (@command);
    END;

IF @frag >= 30.0
    BEGIN;
    SELECT @command = 'ALTER INDEX ' + @indexname +' ON ' + @schemaname + '.' + @objectname + ' REBUILD';
    IF @partitioncount > 1
        SELECT @command = @command + ' PARTITION=' + CONVERT (CHAR, @partitionnum);
    EXEC (@command);
    END;
PRINT 'Executed ' + @command;

FETCH NEXT FROM partitions INTO @objectid, @indexid, @partitionnum, @frag;
END;
-- Close and deallocate the cursor.
CLOSE partitions;
DEALLOCATE partitions;

-- drop the temporary table
IF EXISTS (SELECT name FROM sys.objects WHERE name = 'work_to_do')
    DROP TABLE work_to_do;
GO
 


  总结

  索引的维护是有参考依据的应该根据具体的碎片情况以及是否需要联机操作等需求,采用合理的维护方法自动化的索引维护策略是可行的

 

    黑客防线网安服务器维护方案本篇连接:http://www.rongsen.com.cn/show-11004-1.html
网站维护教程更新时间:2012-03-21 03:13:43  【打印此页】  【关闭
我要申请本站N点 | 黑客防线官网 |  
专业服务器维护及网站维护手工安全搭建环境,网站安全加固服务。黑客防线网安服务器维护基地招商进行中!QQ:29769479

footer  footer  footer  footer