MySQL slow query log and MySQL slow log

MySQL slow query log and MySQL slow log

Lab environment:
OS X EI Captian + MySQL 5.7

1. Configure MySQL to automatically record slow query logs

View the variable, that is, the configuration information.

show (global) variables like '%slow_query%'

Modify variable:

Set global variable name = Value

Variables related to slow query logs:

Whether to enable the slow query log slow_query_log = OFF long_query_time = 10 maximum time limit. If the time limit is exceeded, record slow_query_log_file =/usr/slow. log File Location log_queries_not_using_indexes = OFF whether to record searches without Indexes

Enable the slow query log first:

Bytes

Modify query time:

Bytes

The remaining two global variables are the default values for log paths and records without indexes.

Ii. View MySQL slow query logs

You can directly view:

vim /usr/local/var/mysql/DyanLideMacBook-Air-slow.log

Bytes

You can also usemysqldumpslowView slow query logs:

mysqldumpslow -s at -a  /usr/local/var/mysql/DyanLideMacBook-Air-slow.log

View helpmysqldumpslow --help:

Bytes

Translation:

-- Verbose version -- debug debugging -- help-v version-d debugging mode-s ORDER sorting mode al: average lock time ar: average rows sent at: average query time default c: count l: lock time r: rows sent t: query time-r reverse order. The default reverse order of the file-t NUM shows the first N-a. Do not convert the number in SQL to N, converting string to S-l in total time does not subtract lock time