only seeking row 1 but getting row 2 also

  • I need the Max record (based on entered date) from two tables to compare results.

    I made  two table, each with a Row Number.

    then, I run this......

    select * from #tmpSTP P

    left join #tmpZATS Z

    on P.Tracker_PSYH = Z.ZATS_PSYH

    and P.RowNum = 1

    and Z.RowNum = 1

    But i get row twos from P.

    Is there something silly i don't see??

  • The problem was you had P.RowNum=1 as part of the left join.

    Try this instead:

    select * 
    from #tmpSTP P
    left join #tmpZATS Z
    on P.Tracker_PSYH = Z.ZATS_PSYH
    and Z.RowNum = 1
    where P.RowNum = 1
  • Is this a many-to-many join?

    P.Tracker_PSYH = Z.ZATS_PSYH

    The absence of evidence is not evidence of absence.
    Martin Rees

    You can lead a horse to water, but a pencil must be lead.
    Stan Laurel

  • without seeing the table structure or the data it is returning we will struggle to help

    have you thought about using Row_number() over (partition by … order by …) as rn

    add this to your query and you can just add in "where rn=1"

    It's not the exact code you need (I can't see your database or understand how the table structures relate) but that's how I normally get round that issue.

    if you use a date field in the order by section and the 2 records have the same date then you might not get the record you want.. you may have to add another field to the order by section of the rownum function

     

    MVDBA

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