RE: tsql NOT using INDEX when parameter value in use

SSC Guru

Points: 323507

February 4, 2014 at 7:02 am

what is the definition of the index?

your query has three columns in the WHERE statement, is the index on all three columns?

since you are doing SELECT *, at a minimum, there's going to be a key lookup to get the other columns, so the optimizer might decide the cost is less to use the clustered index; more details on the existing indexes is needed i think.

WHERE (SourceID = 'CCH')

AND ([RowUpdateDateTime] >= @RefreshDate)

AND (NOT [ResultDateTime] IS NULL)

Lowell

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