# ROLLBACK PREPARED

ROLLBACK PREPARED — cancel a transaction that was earlier prepared for two-phase commit

### Synopsis

```
ROLLBACK PREPARED transaction_id
```

### Description

`ROLLBACK PREPARED` rolls back a transaction that is in prepared state.

### Parameters

*`transaction_id`*

The transaction identifier of the transaction that is to be rolled back.

### Notes

To roll back a prepared transaction, you must be either the same user that executed the transaction originally, or a superuser. But you do not have to be in the same session that executed the transaction.

This command cannot be executed inside a transaction block. The prepared transaction is rolled back immediately.

All currently available prepared transactions are listed in the [`pg_prepared_xacts`](https://www.postgresql.org/docs/13/view-pg-prepared-xacts.html) system view.

### Examples

Roll back the transaction identified by the transaction identifier `foobar`:

```
ROLLBACK PREPARED 'foobar';
```

### Compatibility

`ROLLBACK PREPARED` is a PostgreSQL extension. It is intended for use by external transaction management systems, some of which are covered by standards (such as X/Open XA), but the SQL side of those systems is not standardized.

### See Also

[PREPARE TRANSACTION](https://www.postgresql.org/docs/13/sql-prepare-transaction.html), [COMMIT PREPARED](https://www.postgresql.org/docs/13/sql-commit-prepared.html)


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