Error code
PostgreSQL 53300
POSTGRESQL53300
Database Error Code· An error code returned by a database server such as PostgreSQL or MySQL.
What it means
too_many_connections — all connection slots are taken.
How to fix it
- Add a connection pooler such as PgBouncer in front of the database.
- Increase max_connections in postgresql.conf and restart the server (requires a service restart).
- Audit long-running idle sessions and close them with pg_terminate_backend().
Not affiliated with PostgreSQL. Answer summarized from the manufacturer's manual linked above; consult that source for the authoritative procedure.
More PostgreSQL codes
- 08001sqlclient_unable_to_establish_sqlconnection — initial connection refused
- 08006connection_failure — the connection to the server broke
- 0A000feature_not_supported — the requested feature is not implemented
- 22001string_data_right_truncation — a value is too long for the column
- 22003numeric_value_out_of_range — a number exceeds the column's storage range
- 22P02invalid_text_representation — a string could not be parsed into the target type
- 23502not_null_violation — a required column received no value
- 23503foreign_key_violation — the referenced row does not exist
- 23505unique_violation — a row with this key already exists
- 23514check_violation — a row failed a table check constraint
- 25P02in_failed_sql_transaction — the current transaction has already failed
- 28000invalid_authorization_specification — the role is not permitted to connect