Improving OPNQRY Performance:

You can improve OPNQRYF performance in an interactive session by stopping status display. This is very useful when querying a very large database.
Execute following CL command before running the query:
CHGJOB STSMSG(*NONE)
This will stop displaying status message at the bottom of your screen.
To reactivate the status message display use the following command at the end of CL program:
CHGJOB STSMSG(*NORMAL)