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

SSC Guru

Points: 186127

July 15, 2013 at 5:23 am

None of the existing NC indexes are covering.

Create the new index. Change the order of the key columns if necessary.

Then monitor index usage, the cost of maintaining the indexes against the benefit of usage. Ask if you are unsure how to do this.

You may find that queries currently using IX_RESULT_SAMPLE_NUMBER or IX_RESULT_STATUS use the new index instead.

^{“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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