Postgres-XC 0.9.7 Documentation | ||||
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Note: The following description applies both to Postgres-XC and PostgreSQL if not described explicitly.
The view pg_prepared_xacts displays information about transactions that are currently prepared for two-phase commit (see PREPARE TRANSACTION for details).
pg_prepared_xacts contains one row per prepared transaction. An entry is removed when the transaction is committed or rolled back.
Table 45-62. pg_prepared_xacts Columns
Name | Type | References | Description |
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transaction | xid | Numeric transaction identifier of the prepared transaction | |
gid | text | Global transaction identifier that was assigned to the transaction | |
prepared | timestamp with time zone | Time at which the transaction was prepared for commit | |
owner | name | pg_authid.rolname | Name of the user that executed the transaction |
database | name | pg_database.datname | Name of the database in which the transaction was executed |
When the pg_prepared_xacts view is accessed, the internal transaction manager data structures are momentarily locked, and a copy is made for the view to display. This ensures that the view produces a consistent set of results, while not blocking normal operations longer than necessary. Nonetheless there could be some impact on database performance if this view is frequently accessed.