参考sys.dm_db_index_physical_stats
检查索引碎片情况
1.SELECT 2.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 fra 7.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 function 24.– and convert object and index IDs to names. 25.SELECT 26.object_id AS objectid, 27.index_id AS indexid, 28.partition_number AS partitionnum, 29.avg_fragmentation_in_percent AS frag 30.INTO #work_to_do 31.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 NEXT 41.FROM partitions 42.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 o 46.JOIN sys.schemas as s ON s.schema_id = o.schema_id 47.WHERE o.object_id = @objectid; 48.SELECT @indexname = QUOTENAME(name) 49.FROM sys.indexes 50.WHERE object_id = @objectid AND index_id = @indexid; 51.SELECT @partitioncount = count (*) 52.FROM sys.partitions 53.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 < 30.0 56.SET @command = N‘ALTER INDEX ‘ + @indexname + N‘ ON ‘ + @schemaname + N‘.' + @objectname + N‘ REORGANIZE'; 57.IF @frag >= 30.0 58.SET @command = N‘ALTER INDEX ‘ + @indexname + N‘ ON ‘ + @schemaname + N‘.' + @objectname + N‘ REBUILD'; 59.IF @partitioncount > 1 60.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
