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@jasonmead
Created August 15, 2012 15:17
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Find missing indexes in SQL Server
PRINT 'Missing Indexes: '
PRINT 'The "improvement_measure" column is an indicator of the (estimated) improvement that might '
PRINT 'be seen if the index was created. This is a unitless number, and has meaning only relative '
PRINT 'the same number for other indexes. The measure is a combination of the avg_total_user_cost, '
PRINT 'avg_user_impact, user_seeks, and user_scans columns in sys.dm_db_missing_index_group_stats.'
PRINT ''
PRINT '-- Missing Indexes --'
SELECT CONVERT (varchar, getdate(), 126) AS runtime,
mig.index_group_handle, mid.index_handle,
CONVERT (decimal (28,1), migs.avg_total_user_cost * migs.avg_user_impact * (migs.user_seeks + migs.user_scans)) AS improvement_measure,
'CREATE INDEX missing_index_' + CONVERT (varchar, mig.index_group_handle) + '_' + CONVERT (varchar, mid.index_handle)
+ ' ON ' + mid.statement
+ ' (' + ISNULL (mid.equality_columns,'')
+ CASE WHEN mid.equality_columns IS NOT NULL AND mid.inequality_columns IS NOT NULL THEN ',' ELSE '' END + ISNULL (mid.inequality_columns, '')
+ ')'
+ ISNULL (' INCLUDE (' + mid.included_columns + ')', '') AS create_index_statement,
migs.*, mid.database_id, mid.[object_id]
FROM sys.dm_db_missing_index_groups mig
INNER JOIN sys.dm_db_missing_index_group_stats migs ON migs.group_handle = mig.index_group_handle
INNER JOIN sys.dm_db_missing_index_details mid ON mig.index_handle = mid.index_handle
WHERE CONVERT (decimal (28,1), migs.avg_total_user_cost * migs.avg_user_impact * (migs.user_seeks + migs.user_scans)) > 10
ORDER BY migs.avg_total_user_cost * migs.avg_user_impact * (migs.user_seeks + migs.user_scans) DESC
PRINT ''
GO
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