SQL SERVER 2008 R2 如何重建索引
参考sys.dm_db_index_physical_stats
检查索引碎片情况
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 | 1.SELECT2.OBJECT_NAME(object_id) as objectname,3.object_id AS objectid,4.index_id AS indexid,5.partition_number AS partitionnum,6.avg_fragmentation_in_percent AS fra7.FROM sys.dm_db_index_physical_stats (DB_ID(), NULL, NULL , NULL, ‘LIMITED')8.WHERE avg_fragmentation_in_percent > 10.0 AND index_id > 0;9. 10.使用脚本中的 sys.dm_db_index_physical_stats 重新生成或重新组织索引 （来源于联机帮助）11. 12.SET NOCOUNT ON;13.DECLARE @objectid int;14.DECLARE @indexid int;15.DECLARE @partitioncount bigint;16.DECLARE @schemaname nvarchar(130);17.DECLARE @objectname nvarchar(130);18.DECLARE @indexname nvarchar(130);19.DECLARE @partitionnum bigint;20.DECLARE @partitions bigint;21.DECLARE @frag float;22.DECLARE @command nvarchar(4000);23.– Conditionally select tables and indexes from the sys.dm_db_index_physical_stats function24.– and convert object and index IDs to names.25.SELECT26.object_id AS objectid,27.index_id AS indexid,28.partition_number AS partitionnum,29.avg_fragmentation_in_percent AS frag30.INTO #work_to_do31.FROM sys.dm_db_index_physical_stats (DB_ID(), NULL, NULL , NULL, ‘LIMITED')32.WHERE avg_fragmentation_in_percent > 10.0 AND index_id > 0;33.– Declare the cursor for the list of partitions to be processed.34.DECLARE partitions CURSOR FOR SELECT * FROM #work_to_do;35.– Open the cursor.36.OPEN partitions;37.– Loop through the partitions.38.WHILE (1=1)39.BEGIN;40.FETCH NEXT41.FROM partitions42.INTO @objectid, @indexid, @partitionnum, @frag;43.IF @@FETCH_STATUS < 0 BREAK;44.SELECT @objectname = QUOTENAME(o.name), @schemaname = QUOTENAME(s.name)45.FROM sys.objects AS o46.JOIN sys.schemas as s ON s.schema_id = o.schema_id47.WHERE o.object_id = @objectid;48.SELECT @indexname = QUOTENAME(name)49.FROM sys.indexes50.WHERE object_id = @objectid AND index_id = @indexid;51.SELECT @partitioncount = count (*)52.FROM sys.partitions53.WHERE object_id = @objectid AND index_id = @indexid;54.– 30 is an arbitrary decision point at which to switch between reorganizing and rebuilding.55.IF @frag < 30.056.SET @command = N‘ALTER INDEX ‘ + @indexname + N‘ ON ‘ + @schemaname + N‘.' + @objectname + N‘ REORGANIZE';57.IF @frag >= 30.058.SET @command = N‘ALTER INDEX ‘ + @indexname + N‘ ON ‘ + @schemaname + N‘.' + @objectname + N‘ REBUILD';59.IF @partitioncount > 160.SET @command = @command + N‘ PARTITION=' + CAST(@partitionnum AS nvarchar(10));61.EXEC (@command);62.PRINT N‘Executed: ‘ + @command;63.END;64.– Close and deallocate the cursor.65.CLOSE partitions;66.DEALLOCATE partitions;67.– Drop the temporary table.68.DROP TABLE #work_to_do;69.GO |