Deleting GDG

Deleting a Generation Data Group (GDG) involves two key aspects: deleting the GDG base and optionally deleting the individual generations (datasets) associated with that GDG.

Deleting Generation -

If we want to delete the individual generations associated with the GDG, we should delete them separately. This can be done either before or after deleting the GDG base.

Scenario - Delete the latest generation.

MATEPK.TEST.GDG
MATEPK.TEST.GDG.G0001V00
MATEPK.TEST.GDG.G0002V00

Code -

----+----1----+----2----+----3----+----4----+----5----+
//MATEPKDG JOB (123),'MTH',CLASS=A,MSGCLASS=A,MSGLEVEL=(1,1),
//             NOTIFY=&SYSUID 
//*
//STEP1    EXEC PGM=IDCAMS
//SYSPRINT DD  SYSOUT=A
//SYSIN    DD  *
  DELETE (MATEPK.TEST.GDG(0)) GDG
/*

SYSPRINT in Spool -

Delete Latest Generation SYSPRINT

Output -

MATEPK.TEST.GDG
MATEPK.TEST.GDG.G0001V00

In the above example, we have deleted the latest generation (MATEPK.TEST.GDG.G0002V00) of the GDG MATEPK.TEST.GDG.

Deleting GDG Base -

To delete a GDG base, we typically use the IDCAMS utility DELETE statement in JCL. DELETE statement uses two parameters: -

  • PURGE parameter deletes the GDG base, even if its retention period has not expired.
  • FORCE parameter is used to delete the GDG base, the model, and all related generations if they exist.

Scenario - Deleting GDG Base.

MATEPK.TEST.GDG
MATEPK.TEST.GDG.G0001V00
MATEPK.TEST.GDG.G0002V00

Code -

----+----1----+----2----+----3----+----4----+----5----+
//MATEPKC  JOB (123),'MTH',CLASS=A,MSGCLASS=A,MSGLEVEL=(1,1),
//             NOTIFY=&SYSUID 
//*
//STEP1    EXEC PGM=IDCAMS
//SYSPRINT DD  SYSOUT=A
//SYSIN    DD  *
  DELETE (MATEPK.TEST.GDG) GDG FORCE
/*

SYSPRINT in Spool -

Delete GDG Base SYSPRINT

Output -

Delete GDG Base OUTPUT

In the above example, we have deleted the base (MATEPK.TEST.GDG.G0002V00) and all its generations that are currently on it.