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The information of the wait events that are occurring in the PostgreSQL instance can be get now. Waiting column is deleted from pg_stat_activity catalog, wait_event_type columns and wait_event column are added. The wait_event_type column contains the following values. **Table 26.** The value of wait\_event\_type column | Columns value | Description | | --- | --- | | LWLockNamed | Waiting by a particular lightweight lock | | LWLockTranche | Waiting by the lightweight lock for the group | | Lock | Waiting by weight lock (LOCK TABLE statement etc) | | BufferPin | PIN waiting for the buffer | Please refer to the following URL for more information. [http://www.postgresql.org/docs/9.6/static/monitoring-stats.html](http://www.postgresql.org/docs/9.6/static/monitoring-stats.html) **Example 40.** Waiting by two LOCK TABLE IN EXCLUSIVE statements ```text postgres=> SELECT pid, wait_event_type, wait_event FROM pg_stat_activity WHERE pid=4070 ; pid | wait_event_type | wait_event ------+-----------------+------------ 4070 | Lock | relation (1 row) ``` **Example 41.** Waiting by SELECT FOR UPDATE statement and UPDATE statement ```text postgres=> SELECT pid, wait_event_type, wait_event FROM pg_stat_activity WHERE pid=4070 ; pid | wait_event_type | wait_event ------+-----------------+--------------- 4070 | Lock | transactionid (1 row) ```