• Yes, thanks.

    (

    select top 1 (sm2.SalesOrder)

    from SorDetail sd2

    left join SorMaster sm2

    on sm2.SalesOrder = sd2.SalesOrder

    where sd2.LoadNumber = sd.LoadNumber

    and sm2.Customer = ar.Customer

    )

    Top of what exactly, it's missing ORDER BY.

    “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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