39000ERRORTier 2 — Caution✅ HIGH confidence

external routine invocation exception

Category: External Routine Invocation ExceptionVersions: All Postgres versions

What this means

SQLSTATE 39000 is the generic external routine invocation exception code raised when there is an error invoking an external routine (a function written in an external language such as PL/Python, PL/Perl, or C).

Why it happens

1The external language runtime fails to invoke the function
2The function raises an unhandled exception that is caught at the invocation layer

How to reproduce

External routine invocation failure.

trigger — this will ERROR

ERROR: external routine invocation exception

Fix 1: Add error handling inside the external function

When 39000 is raised by an external function.

fix

Why this works

Wrap the function body with language-appropriate error handling (try/except in Python, eval{} in Perl, PG_TRY/PG_CATCH in C) to capture and report errors with meaningful messages.

Sources

📚 Official docs: https://www.postgresql.org/docs/current/errcodes-appendix.html

🔧 Source ref: Class 39 — External Routine Invocation Exception

Confidence assessment

✅ HIGH confidence

Standard SQLSTATE. Stable across versions.