PURGE_LOG()¶
PURGE_LOG() deletes logs recorded in MatrixOne database system tables.
Description¶
PURGE_LOG() deletes logs recorded in MatrixOne database system tables. Returning 0 means the deletion is successful; if the deletion fails, an error message will be returned.
Note
Only the root user (cluster administrator with MOADMIN privilege) can execute the PURGE_LOG() function for log deletion.
Syntax¶
> PURGE_LOG('sys_table_name', 'date')
Arguments¶
Arguments |
Description |
|---|---|
‘sys_table_name’ |
Currently, there are only three system tables that can be deleted: metric, rawlog, and statement_info. |
‘date’ |
Select a date and delete logs generated before that date. |
Note
MatrixOne has only three system log tables: metric, rawlog, and statement_info. For more information about these three tables, please refer to MatrixOne System Database and Tables.
Examples¶
Example 1:
-- Delete the statement_info type logs before 2023-06-30
mysql> select purge_log('statement_info', '2023-06-30') a;
+------+
| a |
+------+
| 0 |
+------+
1 row in set (0.01 sec)
Example 2:
-- Query the time and quantity of metric log collection
mysql> select date(collecttime), count(1) from system_metrics.metric group by date(collecttime);
+-------------------+----------+
| date(collecttime) | count(1) |
+-------------------+----------+
| 2023-07-07 | 20067 |
| 2023-07-06 | 30246 |
| 2023-07-05 | 27759 |
+-------------------+----------+
3 rows in set (0.00 sec)
-- Delete rawlog, statement_info, and metric logs before 2023-07-06
mysql> select purge_log('rawlog, statement_info, metric', '2023-07-06');
+-------------------------------------------------------+
| purge_log(rawlog, statement_info, metric, 2023-07-06) |
+-------------------------------------------------------+
| 0 |
+-------------------------------------------------------+
1 row in set (0.33 sec)
-- Query the number of metric logs for the three days of 2023-07-05, 2023-07-06 and 2023-07-07 again
mysql> select date(collecttime), count(1) from system_metrics.metric group by date(collecttime);
+-------------------+----------+
| date(collecttime) | count(1) |
+-------------------+----------+
| 2023-07-06 | 30246 |
| 2023-07-07 | 20121 |
+-------------------+----------+
2 rows in set (0.01 sec)