Note
- The view was introduced in OceanBase Database V4.3.5 for V4.3.x.
- The view was introduced in OceanBase Database V4.2.2 for V4.2.x.
Purpose
The DBA_WR_EVENT_NAME view displays the names of tenant-level wait events persisted in the current tenant.
Columns
| Column | Type | Nullable? | Description |
|---|---|---|---|
| EVENT_ID | NUMBER(38) | NO | Wait event ID |
| EVENT_NAME | VARCHAR2(64) | YES | Wait event name |
| PARAMETER1 | VARCHAR2(64) | YES | Name of wait event parameter 1 |
| PARAMETER2 | VARCHAR2(64) | YES | Name of wait event parameter 2 |
| PARAMETER3 | VARCHAR2(64) | YES | Name of wait event parameter 3 |
| WAIT_CLASS_ID | NUMBER(38) | YES | ID of wait event category |
| WAIT_CLASS | VARCHAR2(64) | YES | Name of wait event category |
The following table describes the wait event categories and their corresponding wait event IDs in the WAIT_CLASS column of the view.
| Wait event category | Wait event ID | Description |
|---|---|---|
| OTHER | 100 | Wait events that do not belong to other categories |
| APPLICATION | 101 | Wait events caused by client-side code |
| CONFIGURATION | 102 | Wait events caused by insufficient resource configurations of the database or instance |
| ADMINISTRATIVE | 103 | Wait events caused by commands entered by the database administrator, which make users wait |
| CONCURRENCY | 104 | Wait events caused by waiting for internal database resources |
| COMMIT | 105 | Wait events related to log commits |
| IDLE | 106 | Wait events for sessions that are idle and waiting for tasks |
| NETWORK | 107 | Wait events related to network communication |
| USER_IO | 108 | Wait events caused by waiting for user I/O |
| SYSTEM_IO | 109 | Wait events caused by waiting for I/O by background processes |
| CLUSTER | 111 | Wait events related to clusters |
Sample query
obclient [SYS]> SELECT * FROM SYS.DBA_WR_EVENT_NAME WHERE ROWNUM = 1;
The query result is as follows:
+----------+-----------------------------------+------------+------------+------------+---------------+-------------+
| EVENT_ID | EVENT_NAME | PARAMETER1 | PARAMETER2 | PARAMETER3 | WAIT_CLASS_ID | WAIT_CLASS |
+----------+-----------------------------------+------------+------------+------------+---------------+-------------+
| 0 | latch: latch wait queue lock wait | address | number | tries | 104 | CONCURRENCY |
+----------+-----------------------------------+------------+------------+------------+---------------+-------------+
1 row in set