I am face to a problem of performance and I don't know if the solution I took is good or not.
In a program we read a directory and we read each files. Files contain users ID maybe some maybe all table USR02 (ca. 300.000 users).
For each file I need to consult table USR01 / USR21 / ADRP / ADCP / ADR6.
According to you is it better to do a FOR ALL ENTRIES at the begining of a loop (inside the loop for previous tables) or to use SELECT SINGLE on each table during the loop?
I took option of SELECT SINGLE but I do not know if SELECT FOR ALL ENTRIES (for 5 tables) within loop and using after hashed tables would be better or not?
I am lost!
Thanks for your help!