Dynamic Result Sets Returned — SQLSTATE 0100C

SQLSTATE 0100C condition dynamic_result_sets_returned class 01 — Warning severity WARNING
Reproduced & verified on PostgreSQL 14.23, 15.18, 16.14, 17.10 and 18.4 — identical message on every version.
Last reviewed 29 May 2025 · Reproduced live with the SQL on this page.

! Symptoms Free

The server reports SQLSTATE 0100C (dynamic_result_sets_returned), a condition in the Warning class.

  • The error is written to the server log and returned to the client carrying SQLSTATE 0100C.
  • Any driver (libpq, JDBC, psycopg, npgsql, pgx) surfaces this code in its error object so you can branch on it programmatically.

1 Environment & reproduce Free

Severity: WARNING  |  PostgreSQL versions: 12, 13, 14, 15, 16, 17

Reproduce with the exact statement and read the full message in the server log (raise log_min_messages / set log_min_error_statement for more context).

? Root cause Free

0100C belongs to Class 01 — Warning. In this class, the statement succeeded but the server attached a warning.

The first two characters (01) identify the error class, so application code can match the whole class via 01000 when the specific code is not needed.

3 Recovery & verify Free

Read the warning text — the statement completed, but review the data or query it flagged (truncation, deprecated feature, eliminated nulls) before relying on the result.

Reference: PostgreSQL error codes — Class 01 (Warning).