一、查看慢查询日志是否开启:
show VARIABLES LIKE '%slow_query%';
+---------------------+-------------------------------------------------------------------+ | Variable_name | Value | +---------------------+-------------------------------------------------------------------+ | slow_query_log | ON | | slow_query_log_file | D:/javasoft/mysql-8.0.21-winx64/mysql-8.0.21-winx64/data/slow.log | +---------------------+-------------------------------------------------------------------+
我的mysql已开启慢查询日志。
二、开启方式:
在mysql配置文件中添加如下配置(配置修改后需重启mysql服务):
#开启慢查询 slow_query_log = ON #慢查询日志文件 slow_query_log_file = D:/javasoft/mysql-8.0.21-winx64/mysql-8.0.21-winx64/data/slow.log #慢查询时间定义 long_query_time = 5
三、测试慢查询日志生效:
执行如下耗时操作:
SELECT SLEEP(5);
查看慢查询日志文件,即D:/javasoft/mysql-8.0.21-winx64/mysql-8.0.21-winx64/data/slow.log内容:
# Time: 2021-08-10T14:54:34.804101Z # User@Host: root[root] @ localhost [127.0.0.1] Id: 9 # Query_time: 5.009142 Lock_time: 0.000000 Rows_sent: 1 Rows_examined: 1 SET timestamp=1628607269; SELECT SLEEP(5);