SQL has been a major game changer in the RPG programming world.
I first played with it back the olden days of RPG3 and RPG400 when we were all wrapped up in using Commitment Control. Because of that, we still have to tell the program not to use commitment if we don't want to use it. The easiest way is to enter the create parameter of COMMIT(*NONE) thing so it turns it off after the first commit without the isolation level nonsense. But, you can also use embedded SQL in RPG4 programs without journaling your files.
Just specify COMMIT *NONE in the compile command or add a SET OPTION statement at the beginning of the program:
RPG3/400
C/EXEC SQL SET OPTION COMMIT = *NONE C/END-EXEC
RPGLE:
Exec SQL SET OPTION COMMIT = *NONE;
Easy Peasy, Lemon Squeezy.