• Equality predicates first (ComponentID, IsActive, SampleStatusID), then inequality predicates.

    If ISActive is the same everywhere, better to remove it from the query, or make the index filtered. If you remove it from the index, you'll no longer have a covering index and will get lookups (or scans)

    Gail Shaw
    Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
    SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability

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