PostgreSQL Error Reference

Every error, explained

SQLSTATE codes, condition names, root causes, diagnostic queries, and recovery steps — structured for engineers running PostgreSQL in production.

3908 errors documentedFree diagnostics on every pageAll PG versions covered

Showing 3672 of 3908 errors

55006 ERROR

cannot … “…” because it is being used by active queries in this ses… — 55006

object_in_use

PostgreSQL error "cannot … "…" because it is being used by active queries in this session" (SQLSTATE 55006, object_in_use): what it means, common causes, and how to fix it.

Object Not In Prerequisite State
55006 ERROR

cannot … “…” because it has pending trigger events — 55006

object_in_use

PostgreSQL error "cannot … "…" because it has pending trigger events" (SQLSTATE 55006, object_in_use): what it means, common causes, and how to fix it.

Object Not In Prerequisite State
55006 ERROR

aborting because lock on relation “…” is not available — 55006

object_in_use

PostgreSQL error "aborting because lock on relation "…" is not available" (SQLSTATE 55006, object_in_use): what it means, common causes, and how to fix it.

Object Not In Prerequisite State
55006 ERROR

directory “…” already in use as a tablespace — 55006

object_in_use

PostgreSQL error "directory "…" already in use as a tablespace" (SQLSTATE 55006, object_in_use): what it means, common causes, and how to fix it.

Object Not In Prerequisite State
55006 ERROR

current user cannot be dropped — 55006

object_in_use

PostgreSQL error "current user cannot be dropped" (SQLSTATE 55006, object_in_use): what it means, common causes, and how to fix it.

Object Not In Prerequisite State
55006 ERROR

session user cannot be dropped — 55006

object_in_use

PostgreSQL error "session user cannot be dropped" (SQLSTATE 55006, object_in_use): what it means, common causes, and how to fix it.

Object Not In Prerequisite State
55006 ERROR

could not drop replication origin with ID n, in use by PID n — 55006

object_in_use

PostgreSQL error "could not drop replication origin with ID n, in use by PID n" (SQLSTATE 55006, object_in_use): what it means, common causes, and how to fix it.

Object Not In Prerequisite State
55006 ERROR

replication origin with ID n is already active for PID n — 55006

object_in_use

PostgreSQL error "replication origin with ID n is already active for PID n" (SQLSTATE 55006, object_in_use): what it means, common causes, and how to fix it.

Object Not In Prerequisite State
55006 ERROR

replication origin with ID n is already active in another process — 55006

object_in_use

PostgreSQL error "replication origin with ID n is already active in another process" (SQLSTATE 55006, object_in_use): what it means, common causes, and how to fix it.

Object Not In Prerequisite State
55006 ERROR

replication origin with ID n is not active for PID n — 55006

object_in_use

PostgreSQL error "replication origin with ID n is not active for PID n" (SQLSTATE 55006, object_in_use): what it means, common causes, and how to fix it.

Object Not In Prerequisite State
55006 ERROR

database “…” is being accessed by other users — 55006

object_in_use

PostgreSQL error "database … is being accessed by other users — 55006" (SQLSTATE 55006): what it means, common causes, and how to fix it.

Object Not In Prerequisite State
55006 ERROR

replication slot “…” is active for PID N — 55006

object_in_use

PostgreSQL error "replication slot … is active for PID N — 55006" (SQLSTATE 55006): what it means, common causes, and how to fix it.

Object Not In Prerequisite State
55P02 ERROR

Cant Change Runtime Param — SQLSTATE 55P02

cant_change_runtime_param

SQLSTATE 55P02 (cant_change_runtime_param): The object is not in a state that permits the operation.

Object Not In Prerequisite State
55P02 ERROR

parameter “…” cannot be changed without restarting the server — 55P02

cant_change_runtime_param

PostgreSQL error "parameter "…" cannot be changed without restarting the server" (SQLSTATE 55P02): what it means, common causes, and how to fix it.

Object Not In Prerequisite State
55P02 ERROR

parameter “…” cannot be changed now — 55P02

cant_change_runtime_param

PostgreSQL error "parameter "…" cannot be changed now" (SQLSTATE 55P02): what it means, common causes, and how to fix it.

Object Not In Prerequisite State
55P02 ERROR

function can only be called when server is in binary upgrade mode — 55P02

cant_change_runtime_param

PostgreSQL error "function can only be called when server is in binary upgrade mode" (SQLSTATE 55P02, cant_change_runtime_param): what it means, common causes, and how to fix it.

Object Not In Prerequisite State
55P02 ERROR

parameter “…” cannot be changed — 55P02

cant_change_runtime_param

PostgreSQL error "parameter "…" cannot be changed" (SQLSTATE 55P02, cant_change_runtime_param): what it means, common causes, and how to fix it.

Object Not In Prerequisite State
55P02 ERROR

parameter “…” cannot be changed without restarting the server — 55P02

cant_change_runtime_param

PostgreSQL error "parameter … cannot be changed without restarting the server — 55P02" (SQLSTATE 55P02): what it means, common causes, and how to fix it.

Object Not In Prerequisite State
55P03 ERROR

Lock Not Available — SQLSTATE 55P03

lock_not_available

A requested lock could not be obtained (NOWAIT or lock_timeout).

Object Not In Prerequisite State
55P03 ERROR

could not obtain lock on relation “…” — 55P03

lock_not_available

PostgreSQL error "could not obtain lock on relation "…"" (SQLSTATE 55P03): what it means, common causes, and how to fix it.

Object Not In Prerequisite State
55P03 ERROR

canceling statement due to lock timeout — 55P03

lock_not_available

PostgreSQL error "canceling statement due to lock timeout" (SQLSTATE 55P03): what it means, common causes, and how to fix it.

Object Not In Prerequisite State
55P03 ERROR

could not obtain lock on row in relation “…” — 55P03

lock_not_available

PostgreSQL error "could not obtain lock on row in relation … — 55P03" (SQLSTATE 55P03): what it means, common causes, and how to fix it.

Object Not In Prerequisite State
55P03 ERROR

canceling statement due to lock timeout — 55P03

lock_not_available

PostgreSQL error "canceling statement due to lock timeout — 55P03" (SQLSTATE 55P03): what it means, common causes, and how to fix it.

Object Not In Prerequisite State
55P04 ERROR

Unsafe New Enum Value Usage — SQLSTATE 55P04

unsafe_new_enum_value_usage

A newly added enum value cannot be used yet in the same transaction.

Object Not In Prerequisite State