SQLServer 表的索引碎片查询和处理(数据库索引碎片如何整理)这都可以

随心笔谈2年前发布 编辑
154 0
🌐 经济型:买域名、轻量云服务器、用途:游戏 网站等 《腾讯云》特点:特价机便宜 适合初学者用 点我优惠购买
🚀 拓展型:买域名、轻量云服务器、用途:游戏 网站等 《阿里云》特点:中档服务器便宜 域名备案事多 点我优惠购买
🛡️ 稳定型:买域名、轻量云服务器、用途:游戏 网站等 《西部数码》 特点:比上两家略贵但是稳定性超好事也少 点我优惠购买

USE [数据库名]
GO
DECLARE @NoOfPartitions BIGINT;
DECLARE @objectid INT;
DECLARE @indexid INT;
DECLARE @idxname NVARCHAR(255);
DECLARE @objname NVARCHAR(255);
DECLARE @partitionnum BIGINT;
DECLARE @schemaname NVARCHAR(255);
DECLARE @partitions BIGINT;
DECLARE @frag FLOAT;
DECLARE @statement VARCHAR(8000);
— checking existance of the table that we create for temporary purpose
IF OBJECT_ID(‘defrag_work’, ‘U’) IS NOT NULL
DROP TABLE defrag_work;
— Copy the fragmented indexes data into defrag_work table
— All the indexes that has fragmentation < 5 are getting stored into our work table
SELECT [object_id] AS objectid ,
index_id AS indexid ,
partition_number AS partition_no ,
avg_fragmentation_in_percent AS frag
INTO defrag_work
FROM sys.dm_db_index_physical_stats(DB_ID(), NULL, NULL, NULL, ‘LIMITED’)
WHERE avg_fragmentation_in_percent >5.0 and index_id > 0;
— cursor to process the list of partitions
DECLARE partitions CURSOR
FOR
SELECT *
FROM defrag_work;
— Open the cursor.
OPEN partitions;
— Looping through the partitions
FETCH NEXT
FROM partitions
INTO @objectid, @indexid, @partitionnum, @frag;
WHILE @@FETCH_STATUS=0
BEGIN;
SELECT @objname=QUOTENAME(so.name) ,
@schemaname=QUOTENAME(ss.name)
FROM sys.objects AS so
JOIN sys.schemas AS ss ON ss.schema_id=so.schema_id
WHERE so.object_id=@objectid;
SELECT @idxname=QUOTENAME(name)
FROM sys.indexes
WHERE object_id=@objectid
AND index_id=@indexid;
SELECT @NoOfPartitions=COUNT(*)
FROM sys.partitions
WHERE object_id=@objectid
AND index_id=@indexid;

IF (@frag < 30.0) — @frag > 5 is already filtered in our first query, so we need that condition here
BEGIN;
SELECT @statement=’ALTER INDEX ‘ + @idxname + ‘ ON ‘
+ @schemaname + ‘.’ + @objname + ‘ REORGANIZE’;
IF @NoOfPartitions > 1
SELECT @statement=@statement + ‘ PARTITION=’
+ CONVERT (CHAR, @partitionnum);
EXEC (@statement);
END;
IF @frag >=30.0
BEGIN;
SELECT @statement=’ALTER INDEX ‘ + @idxname + ‘ ON ‘
+ @schemaname + ‘.’ + @objname + ‘ REBUILD’;
IF @NoOfPartitions > 1
SELECT @statement=@statement + ‘ PARTITION=’
+ CONVERT (CHAR, @partitionnum);
EXEC (@statement);
END;
PRINT ‘Executed ‘ + @statement;
FETCH NEXT FROM partitions INTO @objectid, @indexid, @partitionnum,
@frag;
END;
— Close and deallocate the cursor.
CLOSE partitions;
DEALLOCATE partitions;
— drop the table
IF OBJECT_ID(‘defrag_work’, ‘U’) IS NOT NULL
DROP TABLE defrag_work;

© 版权声明

相关文章