removing the Key lookup increased the reads.

Posted on 2011-05-12
Last Modified: 2012-05-11
I have added a covering index which removes a Key Lookup. The Cost on the query plan has been reduced from 85% key lookup to 7% covering index.

However, the number of reads went up from 2786 to 2846.

Is this ok?
Question by:Mr_Shaw
    LVL 33

    Accepted Solution

    If it performs noticeably better, then I'd say it's okay.  :)

    Author Closing Comment

    LVL 39

    Expert Comment

    The following link explains you why the reads may be higher but basicaly knightEknight is right - you should look at the query from best performance point of view nut just how many (logical) reads are done.

    You can use set statistics IO on; and set statistics time on; to find out more about your query.

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