PURGE_LOG()

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

1. > 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. Note: ‘sys_table_name’ must be enclosed in quotes.
‘date’ Select a date and delete logs generated before that date. Note: ‘date’ must be enclosed in single quotes.

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:
1. -- Delete the statement_info type logs before 2023-06-30
2. mysql> select purge_log('statement_info', '2023-06-30') a;
3. +------+
4. | a    |
5. +------+
6. | 0    |
7. +------+
8. 1 row in set (0.01 sec)
  • Example 2:
1. -- Query the time and quantity of metric log collection
2. mysql> select date(collecttime), count(1) from system_metrics.metric group by date(collecttime);
3. +-------------------+----------+
4. | date(collecttime) | count(1) |
5. +-------------------+----------+
6. | 2023-07-07        |    20067 |
7. | 2023-07-06        |    30246 |
8. | 2023-07-05        |    27759 |
9. +-------------------+----------+
10. 3 rows in set (0.00 sec)

12. -- Delete rawlog, statement_info, and metric logs before 2023-07-06
13. mysql> select purge_log('rawlog, statement_info, metric', '2023-07-06');
14. +-------------------------------------------------------+
15. | purge_log(rawlog, statement_info, metric, 2023-07-06) |
16. +-------------------------------------------------------+
17. |                                                     0 |
18. +-------------------------------------------------------+
19. 1 row in set (0.33 sec)

21. -- Query the number of metric logs for the three days of 2023-07-05, 2023-07-06 and 2023-07-07 again
22. mysql> select date(collecttime), count(1) from system_metrics.metric group by date(collecttime);
23. +-------------------+----------+
24. | date(collecttime) | count(1) |
25. +-------------------+----------+
26. | 2023-07-06        |    30246 |
27. | 2023-07-07        |    20121 |
28. +-------------------+----------+
29. 2 rows in set (0.01 sec)