Help with Query of Queries...I think

I have the following two queries.

<!--- Get all sessions from category --->
<CFQUERY NAME="rsCatSessions" DATASOURCE="DB">
      SELECT Quiz, QString
      FROM QCat, Quiz
      WHERE mcat = '#URL.cat#' AND scat = '#URL.scat#' AND QCat.QID = Quiz.Qstring
      ORDER BY Quiz ASC
</CFQUERY>

<!--- Get the passed sessions from the category --->
<CFQUERY NAME="rsTakenPass" DATASOURCE="DB">
      SELECT DISTINCT Scores.QString
        FROM Scores
      WHERE Scores.QString = #rsCatSessions.Qstring# AND username = '#session.username#' AND score >= 90
</CFQUERY>

The first query returns a set of ID's that I match up later with their friendly names. The data may look like:
500
501
502
503

The second query compares what was returned in the first query to the scores table to see what has been passed. The data may look like:
500
501

I need help with a query that will show those items that exist in the first query and NOT in the second. That data would look like:
502
503

Thanks in advance!
ActivarAsked:
Who is Participating?
 
Richard QuadlingSenior Software DeveloperCommented:
Hi Activar,


Ultimately, I think this depends upon your database, but try ...

<CFQUERY NAME="rsCatCombined" DATASOURCE="DB">
     SELECT
    Quiz,
    QString
     FROM
    QCat,
    Quiz
     WHERE
    mcat = '#URL.cat#' AND
    scat = '#URL.scat#' AND
    QCat.QID = Quiz.Qstring AND
    QCat.QID NOT IN
        (
        SELECT DISTINCT
            Scores.QString
        FROM
            Scores
        WHERE
            Scores.QString = #rsCatSessions.Qstring# AND
            username = '#session.username#' AND
            score >= 90
        )
     ORDER BY
    Quiz ASC
</CFQUERY>

I'm not sure of the ID columns.

The sub-select needs to ONLY return 1 column of IDs to be rejected. Nothing else. The IDs need to be the ones that are like 500 and 501.


Regards,

Richard Quadling.
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ActivarAuthor Commented:
Richard,

Thanks for the response. While I did not get the results I was looking for from you solution (no fault of your code, just inadequate SQL experience on my end) it did get me looking in the right direction which was just what I needed.

I ended up storing the values of the second query to a list which I qualified the NOT IN statement against. This seems to work like a charm.

<CFQUERY NAME="rsCatCombined" DATASOURCE="DB">
      SELECT Quiz, QString
      FROM QCat, Quiz
      WHERE
      mcat = '#URL.cat#' AND
      scat = '#URL.scat#' AND
        QCat.QID = Quiz.Qstring AND
      QCat.QID NOT IN (#passList#)
      ORDER BY QString ASC
</CFQUERY>

Thanks again
0
 
Richard QuadlingSenior Software DeveloperCommented:
If #passList# is generated by a SELECT statement, then put that statement in where you have #passList#.

This is known as a sub-query.

If you don't actually need #passList# iteslf AND the query works, then you've saved yourself a trip to the server.
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