PG_REPLICATION_SLOTS
PG_REPLICATION_SLOTS displays replication slot information. For details about the columns, see Table 1.
| Name | Type | Description |
|---|---|---|
| slot_name | text | Replication slot name. |
| plugin | text | Name of the output plug-in corresponding to the logical replication slot. |
| slot_type | text | Replication slot type.
|
| datoid | oid | OID of the database where the replication slot resides. |
| database | name | Name of the database where the replication slot resides. |
| active | boolean | Specifies whether the replication slot is activated.
|
| xmin | xid | XID of the earliest transaction that the database must reserve for the replication slot. |
| catalog_xmin | xid | XID of the earliest system catalog-involved transaction that the database must reserve for the logical replication slot. |
| restart_lsn | text | Physical location of the earliest Xlog required by the replication slot. |
| dummy_standby | boolean | Reserved parameter. |
| confirmed_flush | text | Dedicated logical replication slot. The client confirms the location of the received log. |
| confirmed_csn | xid | Dedicated logical replication slot. The client confirms the CSN corresponding to the last transaction in the received log. |
Example:
-- Perform query on the DN. gaussdb=# SELECT * FROM pg_replication_slots; slot_name | plugin | slot_type | datoid | database | active | xmin | catalog_xmin | restart_lsn | dummy_standby | confirmed_flush | confirmed_csn -----------+----------------+-----------+--------+----------+--------+------+--------------+-------------+---------------+-----------------+--------------- dn_6002 | | physical | 0 | | t | | | 0/3622B528 | f | | dn_6003 | | physical | 0 | | t | | | 0/3622B528 | f | | slot_lsn | mppdb_decoding | logical | 131072 | db_test | f | | 66658 | 0/36252350 | f | 0/362523D0 | slot_test | mppdb_decoding | logical | 131072 | db_test | f | | 66658 | 0/36251718 | f | | 10025527 (4 rows) -- Perform query on the CN. gaussdb=# SELECT * FROM pg_replication_slots; slot_name | plugin | slot_type | datoid | database | active | xmin | catalog_xmin | restart_lsn | dummy_standby | confirmed_flush | confirmed_csn -----------+----------------+-----------+--------+----------+--------+------+--------------+-------------+---------------+-----------------+--------------- slot_test | mppdb_decoding | logical | 139264 | db_test | f | | | | f | | (1 row)
When a query is performed on a DN, the confirmed_csn query result of the LSN-based logical replication slot is empty, and the confirmed_flush query result of the CSN-based logical replication slot is empty. When a query is performed on the CN, catalog_xmin, restart_lsn, confirmed_flush, and confirmed_csn of the CSN-based logical replication slot are not displayed and the query result is empty.
