mysql慢查询
查看mysql慢查询日志
-- 慢查询日志
show variables like '%slow_query%';
+---------------------+--------------------------------------+
| Variable_name | Value |
+---------------------+--------------------------------------+
| slow_query_log | OFF |
| slow_query_log_file | /var/lib/mysql/7b32a384231d-slow.log |
+---------------------+--------------------------------------+
2 rows in set
-- 不使用索引查询日志
mysql> show variables like '%log_que%';
+-------------------------------+-------+
| Variable_name | Value |
+-------------------------------+-------+
| log_queries_not_using_indexes | OFF |
+-------------------------------+-------+
1 row in set
-- 查询时间设置,查询超过多少秒才记录
mysql> show variables like '%long_que%';
+-----------------+-----------+
| Variable_name | Value |
+-----------------+-----------+
| long_query_time | 10.000000 |
+-----------------+-----------+
1 row in set
开启慢查询日志
-- 方法一
set global slow_query_log=ON;
set global log_queries_not_using_indexes=ON;
-- 方法二，修改配置文件my.cnf
slow_query_log = ON
slow_query_log_file = /usr/local/mysql/data/slow.log
long_query_time = 1
-- 方法二需要重启
service mysqld restart
慢查询分析工具
mysqldumpslow
pt-query-digest