RE: NC Index Seek 51% and select cost 0%?

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July 15, 2013 at 3:41 am

ananda.murugesan (7/15/2013)
I modified Query as per your suggestion and fetching result 00 seconds..But NC clustred index seek 50% and .. what could be issues?, Need to change index column? and all Inner Join seeks 0%
attched here actual plan

As Gail says, why should that be a problem? The costs are relative - you won't get them all down to 0%!!

The route taken by the optimiser to fetch rows from the RESULT table could be improved by using a covering index and by including a couple more keys. Try this:

create a new index on the RESULT table with keys SAMPLE_NUMBER, STATUS and ANALYSIS,

and included columns UNITS, NAME, NUMERIC_ENTRY. Then check the plan - the order of the keys is significant and is tricky to get right on the first attempt.

Edit - removed RESULTNUMBER, it's the cluster key.

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

For fast, accurate and documented assistance in answering your questions, please read this article.
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