Controlling dynamic allocation of job libraries

You control the dynamic allocation of job libraries by setting the user field JOBLIBRARY at operation level. If you set JOBLIBRARY, its value is preferred over the job-library-read exit (EQQUX002) and EQQJBLIB partitioned data set concatenation.
Note: Carefully examine how often you choose to allocate job libraries dynamically, because this might heavily impact the scheduling process.

For more detailed information, see Defining jobs.