* Raynald Levesque 2002/04/22.

SET MPRINT=no.
DATA LIST LIST /Casenb(A3) FieldD(A8).
BEGIN DATA
001                     x
001                     y
001                     z
002                     x
003                     y
END DATA.

SORT CASES BY casenb.
MATCH FILES FILE=* /BY casenb /LAST=last.

DO IF $CASENUM>1.
IF casenb=LAG(casenb) fieldd=CONCAT(RTRIM(LAG(fieldd)),fieldd).
END IF.
EXECUTE.
* Clean up.
SELECT IF last=1.
ADD FILES FILE=* /DROP=last.