Identifying the Most Costly Indexes

-- Create required table structure only.


-- Note: this SQL must be the same as in the Database loop given in the following step.

SELECT TOP 1

[Maintenance cost] = (user_updates + system_updates)

,[Retrieval usage] = (user_seeks + user_scans + user_lookups)

,DatabaseName = DB_NAME()

,TableName = OBJECT_NAME(s.[object_id])

,IndexName = i.name

INTO #TempMaintenanceCost

FROM sys.dm_db_index_usage_stats s

INNER JOIN sys.indexes i ON s.[object_id] = i.[object_id]

AND s.index_id = i.index_id

WHERE s.database_id = DB_ID()

AND OBJECTPROPERTY(s.[object_id], 'IsMsShipped') = 0

AND (user_updates + system_updates) > 0 -- Only report on active rows.

AND s.[object_id] = -999 -- Dummy value to get table structure.

;



-- Loop around all the databases on the server.

EXEC sp_MSForEachDB 'USE [?];

-- Table already exists.

INSERT INTO #TempMaintenanceCost

SELECT TOP 10

[Maintenance cost] = (user_updates + system_updates)

,[Retrieval usage] = (user_seeks + user_scans + user_lookups)

,DatabaseName = DB_NAME()

,TableName = OBJECT_NAME(s.[object_id])

,IndexName = i.name

FROM sys.dm_db_index_usage_stats s

INNER JOIN sys.indexes i ON s.[object_id] = i.[object_id]

AND s.index_id = i.index_id

WHERE s.database_id = DB_ID()

AND i.name IS NOT NULL -- Ignore HEAP indexes.

AND OBJECTPROPERTY(s.[object_id], ''IsMsShipped'') = 0

AND (user_updates + system_updates) > 0 -- Only report on active rows.

ORDER BY [Maintenance cost] DESC

;

'



-- Select records.

SELECT TOP 10 * FROM #TempMaintenanceCost

ORDER BY [Maintenance cost] DESC

-- Tidy up.

DROP TABLE #TempMaintenanceCost