L1 to L9 used to identify certain fields on control fields and then used to condition which operations are to be processed at detail or total calculation or output time.
In primary file the records will be read and processed from beginning to end. This order is not changed. In fully procedural file the records will be read and processed in any order. The logic flow is controlled by the opcodes in RPG program.
The values stored in array don’t vary. In the other hand, we can store the Different values in same variables at various stages.
File level, Record format level, Field level