Tuesday 14 August 2012

Missing Index From SQL Server MDV

(From
http://blogs.msdn.com/b/bartd/archive/2007/07/19/are-you-using-sql-s-missing-index-dmvs.aspx
)



SELECT

    migs.avg_total_user_cost * (migs.avg_user_impact / 100.0) * (migs.user_seeks + migs.user_scans) AS improvement_measure

    ,db_name(mid.database_id) as DatabaseName

    ,object_name( mid.[object_id], mid.database_id) as TableName

    ,'CREATE INDEX [missing_index_' + CONVERT (varchar, mig.index_group_handle) + '_' + CONVERT (varchar, mid.index_handle)

    + '_' + LEFT (PARSENAME(mid.statement, 1), 32) + ']'

    + ' 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.[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    migs.avg_total_user_cost * (migs.avg_user_impact / 100.0) * (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

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