Sample Exam Questions

From the objective of OSS-DB Exam Gold
- Troubleshooting - Troubleshooting common failures

Sample Question

4.02

Select the one accurate explanation for the following server log.
LOG: server process (PID 21334) was terminated by signal 11: Segmentation fault
DETAIL: Failed process was running: SELECT user_func();

  1. The query was canceled due to a user request.

  2. The pg_cancel_backend function was executed against the process.

  3. The pg_terminate_backend function was executed against the process.

  4. A SIGKILL signal was sent by the OOM Killer.

  5. A SIGSEGV signal was raised by the user_func user-defined function.

※This sample exam is different from those that appear in the actual OSS-DB Exam.
2025/06/02

Answer and Explanation

[Options A, B, C, and D]
For options A, B, C, and D, the server logs would show the following messages, indicating they are not accurate:

A,B
ERROR: canceling statement due to user request
STATEMENT: SELECT user_func();

C
FATAL: terminating connection due to administrator command
STATEMENT: SELECT user_func(); C

D
LOG: server process (PID 21334) was terminated by signal 9: Killed
DETAIL: Failed process was running: SELECT user_func();

[Option E]
A signal 11 (SIGSEGV) is logged when a segmentation fault occurs due to an incorrect memory access, often caused by a user-defined function.
In PostgreSQL version 9.2 or later, the log output also includes the statement the process was executing.
Therefore, option E is accurate.

The correct answer is E.