What is the difference between debugging a background job (with one step) and debugging a program?

Question

I have a background job with only one step. I want to debug that job, so I used the 'JDBG' command in SM37 transaction.

When I do this, the job just runs again, updating the database tables.

So, in this case, what is the difference between debugging the background job in SM37 and running the program with a break point? (except for the SY-BATCH system variable, it is not relevant in this case )

I wanted to debug a background job in the productive system, but using the JDBG method does not seem to help.

Answer 1

Background jobs cannot simply be debugged. They start at a scheduled time, not interactively, are usually run by a different user, such as RFCREMOTE, have system settings like sy-batch = 'X' and don't have access to the SAP GUI. Setting a breakpoint in a program that's run in background mode won't do anything at all.

JDBG simulates what happens when a program is started by the background job scheduler. It effectively runs a copy of the program, not the original program itself. If the program doesn't care for batch settings and user, this will probably not look any different from running the program interactively.

JDBG thus especially does not enable you to "hook into" a job that's already scheduled in a production system.