MS SQL Server má pohled , ze kterého můžete zjistit, které indexy by vám pomohli a zároveň o kolik. Rozhodně zajímavé informace, které z vás zadarmo udělají tuning guru :-D


SELECT CAST(SERVERPROPERTY('ServerName') AS [nvarchar](256)) AS [SQLServer] ,db.[database_id] AS [DatabaseID] ,db.[name] AS [DatabaseName] ,id.[object_id] AS [ObjectID] ,id.[statement] AS [FullyQualifiedObjectName] ,id.[equality_columns] AS [EqualityColumns] ,id.[inequality_columns] AS [InEqualityColumns] ,id.[included_columns] AS [IncludedColumns] ,gs.[unique_compiles] AS [UniqueCompiles] ,gs.[user_seeks] AS [UserSeeks] ,gs.[user_scans] AS [UserScans] ,gs.[last_user_seek] AS [LastUserSeekTime] ,gs.[last_user_scan] AS [LastUserScanTime] ,gs.[avg_total_user_cost] AS [AvgTotalUserCost] ,gs.[avg_user_impact] AS [AvgUserImpact] ,gs.[system_seeks] AS [SystemSeeks] ,gs.[system_scans] AS [SystemScans] ,gs.[last_system_seek] AS [LastSystemSeekTime] ,gs.[last_system_scan] AS [LastSystemScanTime] ,gs.[avg_total_system_cost] AS [AvgTotalSystemCost] ,gs.[avg_system_impact] AS [AvgSystemImpact] ,gs.[user_seeks] * gs.[avg_total_user_cost] * (gs.[avg_user_impact] * 0.01) AS [IndexAdvantage] ,'CREATE INDEX [Missing_IXNC_' + OBJECT_NAME(id.[object_id], db.[database_id]) + '_' + REPLACE(REPLACE(REPLACE(ISNULL(id.[equality_columns], ''), ', ', '_'), '[', ''), ']', '') + CASE WHEN id.[equality_columns] IS NOT NULL AND id.[inequality_columns] IS NOT NULL THEN '_' ELSE '' END + REPLACE(REPLACE(REPLACE(ISNULL(id.[inequality_columns], ''), ', ', '_'), '[', ''), ']', '') + '_' + LEFT(CAST(NEWID() AS [nvarchar](64)), 5) + ']' + ' ON ' + id.[statement] + ' (' + ISNULL(id.[equality_columns], '') + CASE WHEN id.[equality_columns] IS NOT NULL AND id.[inequality_columns] IS NOT NULL THEN ',' ELSE '' END + ISNULL(id.[inequality_columns], '') + ')' + ISNULL(' INCLUDE (' + id.[included_columns] + ')', '') AS [ProposedIndex] ,CAST(CURRENT_TIMESTAMP AS [smalldatetime]) AS [CollectionDate] FROM [sys].[dm_db_missing_index_group_stats] gs WITH (NOLOCK) INNER JOIN [sys].[dm_db_missing_index_groups] ig WITH (NOLOCK) ON gs.[group_handle] = ig.[index_group_handle] INNER JOIN [sys].[dm_db_missing_index_details] id WITH (NOLOCK) ON ig.[index_handle] = id.[index_handle] INNER JOIN [sys].[DATABASES] db WITH (NOLOCK) ON db.[database_id] = id.[database_id] WHERE id.[database_id] >4 -- Remove this to see for entire instance ORDER BY [IndexAdvantage] DESC OPTION (RECOMPILE);

 

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