Substring a date in DDS

[Jeff Crosby <jlcrosby@xxxxxxxxxxxxxxxx>]

I'm trying to create a logical file and use the year and month portions
of an *ISO date field ("INVDT") as a key, like this:

     A          R SHRECORD                  PFILE(*LIBL/SLSHST)
     A*
     A            SLSNR
     A            CUSNR
     A            INVDT
        . . .
        . . . <snip>
        . . .
     A            ONRCUP
     A*
     A            INVYR              I      SST(INVDT 1 4)
     A            INVMO              I      SST(INVDT 6 2)
     A*
     A          K CUSNR
     A          K ITNBR
     A          K INVYR                     DESCEND
     A          K INVMO                     DESCEND

The DDS compiler is hiccupping on the SST statements, saying the field
to be "substringed" must be character or zoned decimal.  Is there a way
to do this?

Thanks.

--
Jeff Crosby
Dilgard Frozen Foods, Inc.
P.O. Box 13369
Ft. Wayne, IN 46868-3369
260-422-7531

The opinions expressed are my own and not necessarily
the opinion of my company.  Unless I say so.