39001ERRORTier 2 — Caution✅ HIGH confidence

invalid SQLSTATE returned

Category: External Routine Invocation ExceptionVersions: All Postgres versions

What this means

SQLSTATE 39001 is raised when an external routine returns or raises a SQLSTATE code that is not a valid 5-character SQLSTATE string.

Why it happens

1An external function raises an error with an invalid SQLSTATE code (not 5 alphanumeric characters)

How to reproduce

External function raising an invalid SQLSTATE.

trigger — this will ERROR

-- PL/Python example:
CREATE FUNCTION bad_sqlstate() RETURNS VOID AS $
plpy.error("bad state", sqlstate="XXXXX99") -- invalid format
$ LANGUAGE plpython3u;

ERROR: invalid SQLSTATE code

Fix 1: Use a valid 5-character SQLSTATE code when raising errors in external functions

When raising custom errors from PL/Python, PL/Perl, or C functions.

fix

Why this works

SQLSTATE codes must be exactly 5 alphanumeric characters. Use a user-defined exception code like P0001 or raise with an existing standard code.

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.