Arrays in RPG ILE
There are three types of arrays:
- The run-time array is loaded by your program while it is running.
- The compile-time array is loaded when your program is created. The initial data becomes a permanent part of your program.
- The prerun-time array is loaded from an array file when your program begins running, before any input, calculation, or output operations are processed.
https://www.ibm.com/docs/en/i/7.4?topic=tables-arrays