I would like to embed a Select statement in a UDF so that I can pop entries from a queue table into a broader query result.  Something like:

     Create FUNCTION Q_Pop1 (TxnType Char(10))

     RETURNS Integer

     LANGUAGE SQL

     CONTAINS SQL

     SPECIFIC Q_Pop1

     CALLED ON NULL INPUT

     SQL SECURITY DEFINER

     COLLATION INVOKER

     INLINE TYPE 1

     RETURN CASE

          when TxnType = 'TypeA' Then Select and Consume top 1 txn_id from QTBL_1

     END;

The use would be something like:

     Sel A.resource, Q_Pop('Deposit') from A where a.avail = 'Y';

From reading manuals and the forums I'm pretty sure that I cannot embed SQL in a UDF.  I thought about burying the SQL inside of some C but if I get a couple thousand rows in the answer set bouncing out to C to connect back to the database to return a row a couple thousand times wouldn't be efficient... 

Any suggestions?

Thanks,

Jim