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