Specific method to view mysql database operation records under Linux
The parameter general_log in MySQL is used to control the opening and closing of the MySQL query log, and the parameter general_log_file is used to control Query the location of the log. If you want to determine whether the MySQL database has query logging enabled, you can use the following command. If general_log is set to ON, the query log will be turned on; if it is set to OFF, the query log will be turned off.
mysql> show variables like '%general_log%'; +------------------+------------------------------+ | Variable_name | Value | +------------------+------------------------------+ | general_log | OFF | | general_log_file | /var/lib/mysql/DB-Server.log | +------------------+------------------------------+ 2 rows in set (0.00 sec)
In addition, MySQL’s query log supports writing to files or writing to data tables. This is controlled by the parameter log_output, as shown below:
mysql> show variables like 'log_output'; +---------------+-------+ | Variable_name | Value | +---------------+-------+ | log_output | FILE | +---------------+-------+ 1 row in set (0.00 sec)
Open MySQL query log
mysql> set global general_log = on; Query OK, 0 rows affected (0.11 sec) mysql> show variables like 'general_log'; +---------------+-------+ | Variable_name | Value | +---------------+-------+ | general_log | ON | +---------------+-------+ 1 row in set (0.02 sec)
Close MySQL query log
mysql> show variables like 'general_log'; +---------------+-------+ | Variable_name | Value | +---------------+-------+ | general_log | ON | +---------------+-------+ 1 row in set (0.01 sec) mysql> set global general_log=off; Query OK, 0 rows affected (0.01 sec) mysql> show variables like 'general_log'; +---------------+-------+ | Variable_name | Value | +---------------+-------+ | general_log | OFF | +---------------+-------+ 1 row in set (0.00 sec)
Set the log output mode to table
If log_output=table is set, the log results will be recorded to the table named gengera_log. The default engine is CSV).
mysql> show variables like 'log_output'; +---------------+-------+ | Variable_name | Value | +---------------+-------+ | log_output | FILE | +---------------+-------+ 1 row in set (0.00 sec) mysql> set global log_output='table'; Query OK, 0 rows affected (0.00 sec) mysql> show variables like 'log_output'; +---------------+-------+ | Variable_name | Value | +---------------+-------+ | log_output | TABLE | +---------------+-------+ 1 row in set (0.01 sec)
View query log information.
mysql> select * from mysql.general_log; +---------------------+---------------------------+-----------+-----------+--------------+----------------------------------+ | event_time | user_host | thread_id | server_id | command_type | argument | +---------------------+---------------------------+-----------+-----------+--------------+----------------------------------+ | 2017-07-06 12:32:05 | root[root] @ localhost [] | 1 | 1 | Query | show variables like 'general%' | | 2017-07-06 12:32:28 | root[root] @ localhost [] | 1 | 1 | Query | show variables like 'log_output' | | 2017-07-06 12:32:41 | root[root] @ localhost [] | 1 | 1 | Query | select * from MyDB.test | | 2017-07-06 12:34:36 | [root] @ localhost [] | 3 | 1 | Connect | root@localhost on | | 2017-07-06 12:34:36 | root[root] @ localhost [] | 3 | 1 | Query | KILL QUERY 1 | | 2017-07-06 12:34:36 | root[root] @ localhost [] | 3 | 1 | Quit | | | 2017-07-06 12:34:51 | root[root] @ localhost [] | 1 | 1 | Query | select * from mysql.general_log | +---------------------+---------------------------+-----------+-----------+--------------+----------------------------------+ 7 rows in set (0.02 sec)
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