SQL Server 索引碎片整理

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SQL Server 索引碎片整理

索引碎片整理的四种方法：

1）删除索引并重建

2）使用 DROP_EXISTING 语句重建索引

3）使用 ALTER INDEX REBUILD 语句重建索引

4）使用 ALTER INDEX REORGANIZE 重新组织索引

--1.查看碎片 SELECT DB_NAME() AS DatbaseName , SCHEMA_NAME(o.Schema_ID) AS SchemaName , OBJECT_NAME(s.[object_id]) AS TableName , i.name AS IndexName , ROUND(s.avg_fragmentation_in_percent, 2) AS [Fragmentation %] , CASE WHEN avg_fragmentation_in_percent > 30 THEN '严重碎片，索引需要重建'

WHEN avg_fragmentation_in_percent >= 5

AND avg_fragmentation_in_percent < 30 THEN '轻度碎片，索引需要重新组织' ELSE '正常状态' END 提示 FROM sys.dm_db_index_physical_stats(DB_ID(), NULL, NULL, NULL, NULL) s INNER JOIN sys.indexes i ON s.[object_id] = i.[object_id] AND s.index_id = i.index_id INNER JOIN sys.objects o ON i.object_id = O.object_id ORDER BY [Fragmentation %] DESC --2.整理碎片（建议在空闲时间运行，尤其不要在生产环境运行） SET NOCOUNT ON DECLARE @Objectid INT , @Indexid INT , @schemaname VARCHAR(100) , @tablename VARCHAR(300) , @ixname VARCHAR(500) , @avg_fip FLOAT , @command VARCHAR(4000) DECLARE IX_Cursor CURSOR FOR SELECT A.object_id , A.index_id , QUOTENAME(SS.NAME) AS schemaname , QUOTENAME(OBJECT_NAME(B.object_id, B.database_id)) AS tablename , QUOTENAME(A.name) AS ixname , B.avg_fragmentation_in_percent AS avg_fip FROM sys.indexes A INNER JOIN sys.dm_db_index_physical_stats(DB_ID(), NULL, NULL, NULL, 'LIMITED') AS B ON A.object_id = B.object_id AND A.index_id = B.index_id INNER JOIN SYS.OBJECTS OS ON A.object_id = OS.object_id INNER JOIN sys.schemas SS ON OS.schema_id = SS.schema_id WHERE B.avg_fragmentation_in_percent > 10

AND B.page_count > 20

AND A.index_id > 0

AND A.IS_DISABLED <> 1 --AND OS.name='book' ORDER BY avg_fip DESC , tablename , ixname OPEN IX_Cursor FETCH NEXT FROM IX_Cursor INTO @Objectid, @Indexid, @schemaname, @tablename, @ixname, @avg_fip WHILE @@FETCH_STATUS = 0 BEGIN --碎片率>5%或<=30%，索引重组 IF @avg_fip < 30.0 SET @command = N'ALTER INDEX ' + @ixname + N' ON ' + @schemaname + N'.' + @tablename + N' REORGANIZE '; --碎片率>=30%，索引重建 IF @avg_fip >= 30.0

AND @Indexid = 1 BEGIN IF EXISTS ( SELECT * FROM SYS.columns WHERE OBJECT_ID = @Objectid AND max_length IN ( -1, 16 ) ) SET @command = N'ALTER INDEX ' + @ixname + N' ON ' + @schemaname + N'.' + @tablename + N' REBUILD '; ELSE SET @command = N'ALTER INDEX ' + @ixname + N' ON ' + @schemaname + N'.' + @tablename + N' REBUILD ' + N' WITH (ONLINE = ON)'; END IF @avg_fip >= 30.0

AND @Indexid > 1 BEGIN IF EXISTS ( SELECT * FROM SYS.index_columns IC INNER JOIN SYS.columns CS ON CS.OBJECT_ID = IC.OBJECT_ID AND CS.column_id = IC.column_id WHERE IC.OBJECT_ID = @Objectid AND IC.index_id = @Indexid AND CS.max_length IN ( -1, 16 ) ) SET @command = N'ALTER INDEX ' + @ixname + N' ON ' + @schemaname + N'.' + @tablename + N' REBUILD '; ELSE SET @command = N'ALTER INDEX ' + @ixname + N' ON ' + @schemaname + N'.' + @tablename + N' REBUILD ' + N' WITH (ONLINE = ON)'; END --打印命令，单独执行 PRINT @command

--直接执行命令 --EXEC(@command) FETCH NEXT FROM IX_Cursor INTO @Objectid, @Indexid, @schemaname,@tablename, @ixname, @avg_fip END CLOSE IX_Cursor DEALLOCATE IX_Cursor

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本文作者：star8521 本文链接：https://www.cnblogs.com/star8521/p/13946784.html

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