• I don't get it. LOL! ^^

    My answer was E.

    Can you help explain below statement?

    "because a nullability check using ISNULL CAN be SARGable if the ISNULL is written correctly"

    Probably, give us a sample of ISNULL not written correctly. ^^

    As far as I know, once we use function in WHERE clause, it will be non-sargable and index seek will not be used anymore.

    Thanks in advance.