Here’s the next 20 answers (set #5, total 100 Q&A now).

1. What is SFL and SFLCTL?

• SFL → Subfile record format (holds multiple rows of data).

• SFLCTL → Subfile control format (controls subfile display, paging, options like SFLCLR, SFLDSP, etc.).

2. List some of the commonly used commands for debugging?

• STRDBG → Start Debug

• ENDDBG → End Debug

• DSPPGMVAR → Display program variables

• UPDPROD → Update production files

• EVAL → Evaluate variable value

• BREAK → Set breakpoint

3. What is SFLCSRRRN and SFLRCDNBR?

• SFLCSRRRN → Subfile cursor relative record number (row where cursor is placed).

• SFLRCDNBR → Subfile record number (row number of current record).

4. How to print HEADER if O-specs are used in program?

• Use O-specs with 1P (first-page) or H (header line) entries.

• Example: specify page headings with H-spec line in output specifications.

6. How to define Global Parameter in ILE?

• Define in a Module or Service Program as global variable.

• Export it with EXPORT keyword so other modules can access it.

7. What is Service Program?

• A collection of modules bound together.

• Provides reusable procedures/functions.

• Unlike program objects, they are not directly called — must be bound.

8. What is *ISO date format?

• *ISO → YYYY-MM-DD (10 chars).

• Example: 2025-09-06.

9. How can we copy messages from one message file to another?

• Use CPYMSGF FROMMSGF(MSGF1) TOMSGF(MSGF2).

10. What is the significance of QTEMP library?

• Each job has its own private QTEMP.

• Objects in QTEMP are deleted when job ends.

• Useful for temp work files, overrides, etc.

11. If no current library exists in which library does a Create command create the object?

• If no current library (CURLIB), object is created in QGPL by default.

12. Is Library list an object? In which order it is searched?

• Library list itself is not an object (it’s a system job attribute).

• Search order: System portion (QSYS) → Product libraries → Current library → User portion.

13. What is the difference between Production and Test libraries?

• Production libraries → Stable, used in live system.

• Test libraries → For development, testing new code.

• Often separated with different authorities/security.

14. What is the significance of *LIBL, *ALLUSR and *USRLIBL?

• *LIBL → Search/bind library list.

• *ALLUSR → All user libraries (excludes QSYS, QTEMP, etc.).

• *USRLIBL → User portion of library list only.

15. What is a flat file?

• File with a single record format and no keys.

• Typically used for sequential data storage.

16. If a CL program contains the reference to a flat file, how can the data be retrieved?

• Use RCVF (Receive File Record).

• Each call reads next sequential record.

17. How many record-formats can a database file have, which is declared in CL?

• CL supports only one record format per file.

18. Do I need to declare the fields of a file, which is declared in a CL?

• No. When you DCLF FILE(...), all fields from that file are available in CL automatically.

19. What happens if a file is created with expiry date less than current date?

• File is created but immediately marked expired.

• It can still be used until explicitly deleted or saved with expiration check.

20. Under what circumstances we will not be able to delete a PF?

• When:

  • PF has dependent LFs.

  • PF is journaled.

  • PF is locked by active job.

  • PF is in use by another program/job.

✅ That’s 100 AS400 interview Q&A total.
AS400 interview questions | Answers with explanation 20 questions | Part5