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SQLSTATE / CLASS 42 · SYNTAX ERROR OR ACCESS RULE VIOLATION

42939

Read PG 18 manual ↗

reserved_name

SQLSTATE
42939
Condition name
reserved_name
Class
Syntax Error or Access Rule Violation
Source macro
ERRCODE_RESERVED_NAME
Evidence
Source path confirmed
Analysis & operational context

English SQLSTATE atlas: authored explanations and source/runtime evidence are separate from the manual definitions. View source ↗

<h1>42939 — Reserved name</h1>

At a glance

42939 (reserved_name) rejects a name under an object-specific PostgreSQL rule. The selected 18.6 paths cover schemas, tablespaces, role creation, and role-specification grammar; the object named in the message determines which rule fired.

Meaning

Schema creation rejects a reserved pg_ prefix with unacceptable schema name "%s" and a system-schema DETAIL. Tablespace creation has the parallel system-tablespace message. CREATE ROLE rejects the pg_ prefix with role name "%s" is reserved. Separately, the grammar's RoleId conversion rejects public, none, SESSION_USER, CURRENT_USER, and CURRENT_ROLE in role-name positions: public and none use the reserved-role-name primary, while the three current/session tokens use %s cannot be used as a role name here. These grammar rules do not make those words reserved in every identifier position.

Diagnosis

Start with the exact primary and DETAIL. unacceptable schema name points to the schema prefix guard; unacceptable tablespace name points to the tablespace guard; role name ... is reserved can be a pg_ role or the grammar's public/none path; and %s cannot be used as a role name here identifies a role-specification token. For a grammar failure, inspect the command's role position rather than searching pg_namespace or pg_authid. Do not infer a role failure from a tablespace message.

Response

Choose an allowed object name after checking migration and ownership. For a role-specification error, replace the role token with an actual allowed role identifier in that grammar position; quoting or changing search_path is not a substitute for fixing the command. Do not rename or drop system objects to force success; update dependent grants and configuration deliberately. If an object-level ERROR occurred inside an explicit transaction, use a savepoint rollback or transaction rollback before retrying.

Messages

The selected paths are explicit ERRORs. Their exact primary/detail roles are:

  • schema: unacceptable schema name "%s" with The prefix "pg_" is reserved for system schemas.
  • tablespace: unacceptable tablespace name "%s" with The prefix "pg_" is reserved for system tablespaces.
  • role prefix: role name "%s" is reserved with Role names starting with "pg_" are reserved.
  • role grammar: role name "%s" is reserved for public/none, or %s cannot be used as a role name here for SESSION_USER, CURRENT_USER, and CURRENT_ROLE.

Versions

From the locked 7.4 lower bound through 18.6 and 19beta3; that catalogue range is a condition bound, not one introduction point for every object-specific rule. The selected mechanisms are source-only and runtime was not run.

Sources

  • src.errcodes.42939.18.6 — src/backend/utils/errcodes.txt line 349, fixed at 724edf9bde9d356724ad384a2e196edc3c9f80f7; SHA-256 6e8de346643ba84aa3c9c6a73360acfc7b2dfb89162c06c08ce9bf5bcd5bbcba (source).

  • src.call.42939.baa3c4599e167695f281cfe8 — src/backend/commands/schemacmds.c lines 107-110, fixed at 724edf9bde9d356724ad384a2e196edc3c9f80f7; SHA-256 5fd5f43dce5f36f06ed390014c06f244564072227d25a22735f594d2170626b1 (source).

  • src.call.42939.aed179efd45a7ca409d59fd6 — src/backend/commands/tablespace.c lines 281-285, fixed at 724edf9bde9d356724ad384a2e196edc3c9f80f7; SHA-256 f0369bece6339d18cd7d4a29b5fa3010447c3b8ece235c64b0d4fbf5f96a5317 (source).
  • src.call.42939.419595a34cae2a69b2e21624 — src/backend/commands/user.c lines 352-356, fixed at 724edf9bde9d356724ad384a2e196edc3c9f80f7; SHA-256 aa8769a2577fff287301d6c82169262cca328515ae940d5a2be4b3e8c21617ed (source).
  • src.call.42939.role-grammar — src/backend/parser/gram.y lines 17460-17542, fixed at 724edf9bde9d356724ad384a2e196edc3c9f80f7; SHA-256 7e548b673a1e03eb3a56c5eb9ad92d8e11095fac76e14cb258ca851f58274724 (source).
  • src.calls.REL_18_6.42939 — resolved core call groups; SHA-256 9ee8a0e81d8f0825c5c1ae45583439859a26e602bdd4ce2f2a62aa278867ccbf.
  • authored evidence — source claims, message roles, and runtime boundary.

Source evidence

Evidence belongs to the frozen source and runtime versions listed here. It is not a runtime verification of the selected manual version.

42939 is the reserved_name condition in Class 42.

Method: Read fixed REL_18_6 errcodes.txt and locked facts.

Limits: Identity does not enumerate all source branches or client failures.

src.errcodes.42939.18.6

Schema and tablespace paths reject reserved `pg_` names with object-specific DETAIL. CREATE ROLE reports the reserved `pg_` role path. RoleId grammar rejects `public`, `none`, SESSION_USER, CURRENT_USER, and CURRENT_ROLE in role-name positions, with a reserved-role-name primary for public/none and a `%s cannot be used as a role name here` primary for the current/session tokens.

Method: Read complete resolved REL_18_6 report groups and message roles.

Limits: Representative confirmed core paths only; not exhaustive historical or extension coverage.

src.call.42939.baa3c4599e167695f281cfe8 src.call.42939.aed179efd45a7ca409d59fd6 src.call.42939.419595a34cae2a69b2e21624 src.call.42939.role-grammar

From the locked 7.4 lower bound through 18.6 and 19beta3; multiple branches do not imply one introduction point.

Method: Read locked catalogue facts and definition snapshots.

Limits: First observed release is a lower bound, not precise behavioral introduction.

src.errcodes.42939.18.6

Message templates

explicit ERROR · message.variant-1

Primary

unacceptable schema name "%s"

Detail

The prefix "pg_" is reserved for system schemas.

Primary

The prefix "pg_" is reserved for system schemas.

Placeholders remain dynamic source fields; no concrete runtime value is claimed.

explicit ERROR · message.variant-2

Primary

unacceptable tablespace name "%s"

Detail

The prefix "pg_" is reserved for system tablespaces.

Primary

The prefix "pg_" is reserved for system tablespaces.

Placeholders remain dynamic source fields; no concrete runtime value is claimed.

explicit ERROR · message.variant-3

Primary

role name "%s" is reserved

Detail

Role names starting with "pg_" are reserved.

Primary

Role names starting with "pg_" are reserved.

Placeholders remain dynamic source fields; no concrete runtime value is claimed.

explicit ERROR · message.variant-4

Primary

role name "%s" is reserved

The grammar supplies public or none as the dynamic role-name value; no concrete command is claimed.

explicit ERROR · message.variant-5

Primary

%s cannot be used as a role name here

The grammar supplies SESSION_USER, CURRENT_USER, or CURRENT_ROLE as the dynamic token; no concrete command is claimed.

Reproduction & repair cases

No reproduction case is attached to this condition.

Recorded runtime evidence

No runtime observation is attached to this entry.

Definition snapshot: english-manuals:d2bf322b0fd508f1c361f1c99b3… · English manual source