log_output參數是指定日誌的存儲方式
阿新 • • 發佈:2017-05-06
file comm mine bash sig 系統資源 date light 解決
log_output=‘FILE‘表示將日誌存入文件,默認值是‘FILE‘ log_output=‘TABLE‘表示將日誌存入數據庫,這樣日誌信息就會被寫入到mysql.slow_log表中.
mysql數據庫支持同時兩種日誌存儲方式,配置的時候以逗號隔開即可,如:log_output=‘FILE,TABLE‘.日誌記錄到系統專用日誌表中,要比記錄到文件耗費更多的系統資源,因此對於需要啟用慢查日誌,又需要比夠獲得更高的系統性能,那麽建議優先記錄到文件.
mysql> show variables like ‘%log_output%‘; +---------------+-------+ | Variable_name | Value | +---------------+-------+ | log_output | FILE | +---------------+-------+ 1 row in set (0.00 sec)
但設置:log_output=‘TABLE‘時,在線查詢的時候,報錯!!!
後來通過下面的設置問題解決:
mysql> show variables like ‘%log_output%‘; +---------------+-------+ | Variable_name | Value | +---------------+-------+ | log_output | TABLE | +---------------+-------+ 1 row in set (0.00 sec) mysql> set global log_output=‘FILE‘; Query OK, 0 rows affected (0.00 sec) mysql> select @@global.log_output; +---------------------+ | @@global.log_output | +---------------------+ | FILE | +---------------------+ 1 row in set (0.00 sec) mysql> set @@global.slow_query_log = ON; Query OK, 0 rows affected (0.00 sec) mysql> set @@global.log_output=‘TABLE‘; Query OK, 0 rows affected (0.00 sec) mysql> show create table mysql.slow_log; +----------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | Table | Create Table | +----------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | slow_log | CREATE TABLE `slow_log` ( `start_time` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP, `user_host` mediumtext NOT NULL, `query_time` time NOT NULL, `lock_time` time NOT NULL, `rows_sent` int(11) NOT NULL, `rows_examined` int(11) NOT NULL, `db` varchar(512) NOT NULL, `last_insert_id` int(11) NOT NULL, `insert_id` int(11) NOT NULL, `server_id` int(10) unsigned NOT NULL, `sql_text` mediumtext NOT NULL ) ENGINE=CSV DEFAULT CHARSET=utf8 COMMENT=‘Slow log‘ | +----------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ 1 row in set (0.00 sec)
mysql> select * from mysql.slow_log limit 4\G; *************************** 1. row *************************** start_time: 2017-05-06 14:13:48 user_host: zabbix[zabbix] @ localhost [] query_time: 00:00:00 lock_time: 00:00:00 rows_sent: 1 rows_examined: 1 db: zabbix last_insert_id: 0 insert_id: 0 server_id: 1 sql_text: SELECT dv.mandatory,dv.optional FROM dbversion dv *************************** 2. row *************************** start_time: 2017-05-06 14:13:48 user_host: zabbix[zabbix] @ localhost [] query_time: 00:00:00 lock_time: 00:00:00 rows_sent: 1 rows_examined: 1 db: zabbix last_insert_id: 0 insert_id: 0 server_id: 1 sql_text: SELECT dv.mandatory,dv.optional FROM dbversion dv *************************** 3. row *************************** start_time: 2017-05-06 14:13:48 user_host: zabbix[zabbix] @ localhost [] query_time: 00:00:00 lock_time: 00:00:00 rows_sent: 1 rows_examined: 1 db: zabbix last_insert_id: 0 insert_id: 0 server_id: 1 sql_text: SELECT dv.mandatory,dv.optional FROM dbversion dv *************************** 4. row *************************** start_time: 2017-05-06 14:13:48 user_host: zabbix[zabbix] @ localhost [] query_time: 00:00:00 lock_time: 00:00:00 rows_sent: 1 rows_examined: 1 db: zabbix last_insert_id: 0 insert_id: 0 server_id: 1 sql_text: SELECT dv.mandatory,dv.optional FROM dbversion dv 4 rows in set (0.00 sec) ERROR: No query specified
mysql> select @@global.slow_query_log; +-------------------------+ | @@global.slow_query_log | +-------------------------+ | 1 | +-------------------------+ 1 row in set (0.00 sec)
log_output參數是指定日誌的存儲方式