• A little more info - this is the same question on MSDN:

    [Quote]I have one simple query to optimize but somehow after creating couple of index this query is still having more logical reads and time.

    DECLARE @CURRENT smalldatetime

    set @current = '6/30/2013'

    select KeyInstn, MAX(dateendedstandard) DateEndedStandard

    from InternalEstimate with (index(AI_OperatorCBGEstimate_HAP))

    where dateendedstandard < @Current and mostrecentsequence = 1 and UpdOperation<2

    group by KeyInstn

    I have created index as

    CREATE NONCLUSTERED INDEX [<Name of Missing Index, sysname,>]

    ON [dbo].[OperateEstimate] ([MostRecentSequence],[DateEndedStandard],[UpdOperation])

    INCLUDE ([KeyInstn])[/quote]

    Is that two different tables or is one of them a view?

    “Write the query the simplest way. If through testing it becomes clear that the performance is inadequate, consider alternative query forms.” - Gail Shaw

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