# 55000 — Object not in prerequisite state

> PostgreSQL SQLSTATE 55000: Object not in prerequisite state (object_not_in_prerequisite_state), source-backed diagnosis and recovery guidance.
---

# 55000 — Object not in prerequisite state

## At a glance {#at-a-glance}

`55000` means the requested operation lacks a required object or server state. This page selects the session-local sequence prerequisite behind `currval`; preload, recovery, and invalid-index paths are separate mechanisms.

<!-- BEGIN SQLSTATE FACTS: generated by scripts/generate.py; do not edit -->

| Field | Value |
| --- | --- |
| SQLSTATE | `55000` |
| Condition | `object_not_in_prerequisite_state` |
| Status | `active` |
| Known present by | `7.4` |
| Locked snapshots | `9.0.23, 9.1.24, 9.2.24, 9.3.25, 9.4.26, 9.5.25, 9.6.24, 10.23, 11.22, 12.22, 13.23, 14.24, 15.19, 16.15, 17.11, 18.6, 19beta3` |
| Macros | `ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE` |
| Aliases | `—` |

<!-- source facts: data/errcodes/55000.json -->
<!-- END SQLSTATE FACTS -->

## Meaning {#meaning}

`currval` is defined per backend session. Creating a sequence, or calling `nextval` in another session, does not initialize the current session. The fixed sequence template is `currval of sequence "%s" is not yet defined in this session` with `ERROR` severity.

Other fixed 55000 paths have different prerequisites. `pg_stat_statements` reports `pg_stat_statements must be loaded via "shared_preload_libraries"`; add the extension to that startup setting and restart the server through the normal configuration procedure. `pg_surgery` reports `recovery is in progress` with detail `Heap surgery functions cannot be executed during recovery.`; wait for recovery to finish or run the operation on the appropriate writable primary. `pgstattuple` reports `index "%s" is not valid`; inspect the index and rebuild it with the appropriate `REINDEX` or migration procedure before using that function. These are object or server-state checks, not permission failures and not interchangeable with the session-local sequence case.

## Diagnosis {#diagnosis}

Check the exact object state and the backend session that owns it. For this path, identify the sequence and verify whether this backend has called `nextval`; a pooled connection that ran `nextval` is a different prerequisite state. In an explicit transaction, a failed `currval` aborts the transaction, so issue `ROLLBACK` or `ROLLBACK TO SAVEPOINT` before repairing it. For other 55000 paths inspect recovery, preload settings, index validity, or object-specific prerequisites.

## Response {#response}

Call `nextval` in the same backend before `currval`, or pass an explicitly known value when that is the intended contract. In autocommit, reconnecting or issuing the next statement is possible because the failed statement's transaction has ended; inside an explicit transaction, recover with a rollback or savepoint before calling `nextval`. Do not treat this as a privilege failure or assume a successful call from a pool’s different connection initializes the current one.

## Observed diagnostics {#messages}

The selected source group is `ERROR` with the dynamic sequence-name template above. Runtime diagnostics named `currval_sequence`; after the failure the autocommit session stayed `IDLE`, and the same session then returned 10 from `nextval` and `currval`.

## Representative case {#case}

The selected registry creates the sequence and then, on one autocommit backend, calls `currval` before any `nextval`, initializes the sequence with `nextval` (returning 10), and reads `currval` again (returning 10). The failing call, repair, and verification are therefore one session-scoped state transition; this case does not test a connection-pool handoff.

<!-- BEGIN SQLSTATE SNIPPET: currval_before_nextval -->

```sql
CREATE SEQUENCE sequence_identifier START WITH 10;
SELECT currval('sequence_regclass');
SELECT nextval('sequence_regclass');
SELECT currval('sequence_regclass')
```

<!-- END SQLSTATE SNIPPET -->

The selected PostgreSQL 18.6 and 10.21 runs passed SQLSTATE, severity, state or disconnect recovery, repair, cleanup, and isolated-target stop assertions. See [`case JSON`](../data/cases/55000.json) and [`authored evidence`](../data/evidence/55000.json).

## Versions {#versions}

The locked catalogue records 55000 from 7.4 through the listed snapshots. The sequence-session case passed on 18.6 and 10.21; these observations do not cover the other 55000 branches or infer every intermediate implementation.

## Related {#related}

- [`55006`](../55006/)
- [`42501`](../42501/)

## Sources {#sources}

- `src.errcodes.18.6` — `src/backend/utils/errcodes.txt` at `724edf9bde9d356724ad384a2e196edc3c9f80f7`; blob SHA-256 `6e8de346643ba84aa3c9c6a73360acfc7b2dfb89162c06c08ce9bf5bcd5bbcba` ([source](https://github.com/postgres/postgres/blob/724edf9bde9d356724ad384a2e196edc3c9f80f7/src/backend/utils/errcodes.txt#L424)).
- `src.currval.18.6` — `src/backend/commands/sequence.c` at `724edf9bde9d356724ad384a2e196edc3c9f80f7`; blob SHA-256 `3e5afe17d5a84862fae502a5481211220368f1d639e9d07ba6f96ee8be92a8d8` ([source](https://github.com/postgres/postgres/blob/724edf9bde9d356724ad384a2e196edc3c9f80f7/src/backend/commands/sequence.c#L884-L887)).
- `src.currval.10.23` — `src/backend/commands/sequence.c` at `02991e79f8f58bc208f05dcc8af0c62dbe0a6ea4`; blob SHA-256 `5510e1266e8d8c548a4318d753392e92e689d348f3353a2aa53d8dea871c44ab` ([source](https://github.com/postgres/postgres/blob/02991e79f8f58bc208f05dcc8af0c62dbe0a6ea4/src/backend/commands/sequence.c#L845-L848)).
- `src.path.0` — `contrib/pg_stat_statements/pg_stat_statements.c` at `724edf9bde9d356724ad384a2e196edc3c9f80f7`, the `shared_preload_libraries` guard ([source](https://github.com/postgres/postgres/blob/724edf9bde9d356724ad384a2e196edc3c9f80f7/contrib/pg_stat_statements/pg_stat_statements.c#L1685-L1687)).
- `src.path.1` — `contrib/pg_surgery/heap_surgery.c` at `724edf9bde9d356724ad384a2e196edc3c9f80f7`, the recovery guard and detail ([source](https://github.com/postgres/postgres/blob/724edf9bde9d356724ad384a2e196edc3c9f80f7/contrib/pg_surgery/heap_surgery.c#L99-L102)).
- `src.path.2` — `contrib/pgstattuple/pgstatindex.c` at `724edf9bde9d356724ad384a2e196edc3c9f80f7`, the invalid-index guard ([source](https://github.com/postgres/postgres/blob/724edf9bde9d356724ad384a2e196edc3c9f80f7/contrib/pgstattuple/pgstatindex.c#L244-L247)).
- `src.calls.REL_18_6` / `src.calls.REL_10_23` — fixed call scans, SHA-256 `9ee8a0e81d8f0825c5c1ae45583439859a26e602bdd4ce2f2a62aa278867ccbf` / `00d16d3eb01b71ccf1b245c8f3102f9d0ec9f36fb02777b8dd1b99fcb263040c`.
- `manifest.55000` / `snippet-registry.55000` — hashes are recorded in `evidence/55000.json` and each selected runtime record.