RE: SQL Question

>Somewhere I heard about user-defined functions. I was wondering if
>somebody has some instructions on programming (rpg)/registering/using
>them. That's if it is possible to do it with qmquery....

Hi Matthias!  Yes, we can do UDF's with QMQRY; no problem.  I have a very
simple example that might get you started.  It returns a numeric value
without any editing.

     h debug dftactgrp(*no) actgrp(*caller)
      * dbgview(*list)

      * Return a numeric value without editing
      * register:

      * CREATE FUNCTION NOEDIT (DECIMAL(30,15))
      * RETURNS VARCHAR(256)
      * RETURNS NULL ON NULL INPUT
      * LANGUAGE RPGLE
      * EXTERNAL NAME 'BUCK/SQLNOEDIT'
      * DETERMINISTIC
      * NO SQL
      * NO EXTERNAL ACTION
      * PARAMETER STYLE SQL
      * DISALLOW PARALLEL

      * execute by:
      *   select noedit(total) from master

     d inpDec          s             30 15
     d outChar         s            256    varying
     d inpInd          s              5i 0
     d outInd          s              5i 0
     d outSQLState     s              5
     d inpFuncName     s            139    varying
     d inpSpecName     s            128    varying
     d outDiagTxt      s             70    varying

     c     *entry        plist
     c                   parm                    inpDec
     c                   parm                    outChar
     c                   parm                    inpInd
     c                   parm                    outInd
     c                   parm                    outSQLState
     c                   parm                    inpFuncName
     c                   parm                    inpSpecName
     c                   parm                    outDiagTxt

     c                   eval      outChar = %editc(inpDec: 'X')

     c                   eval      *inlr = *on

As for reference material, visit
http://publib.boulder.ibm.com/html/as400/v5r1/ic2924/info/rzahf/rzahfms1.htm
and choose one of the UDF examples from the "examples" box.
  --buck