Using dependent variables for migration

Dependent variables can be useful when you are changing the release of some software. One way is to have two copies of each job, but in many cases it is just data set qualifiers that change (for example, from CICS320.LOADLIB to CICS330.LOADLIB. Making the data set qualifier a variable lets you have just one set of jobs, which is important if you make other changes unconnected to the change in release. Your effort in coding variables is rewarded when you next upgrade the software, because the variables are already in the jobs.

Another advantage is that fallback is easier, because you do not have to remember what happened to the old jobs, and what changes must be retroactively made to them.