MySQL enable logging, and view logs

MySQL has the following several logs:

Error log:-log-err

Query log:-log

Slow query log:-log-slow-queries

Update log:-log-update

Binary log:-log-bin

Whether logging is enabled

Mysql>show variables like ' log_% ';

How to know the current log

Mysql> Show master status;

Display binary Log numbers

Mysql> show master logs;

See binary log file with Mysqlbinlog

Shell>mysqlbinlog mail-bin.000001

or Shell>mysqlbinlog mail-bin.000001 | Tail

Specify the output location of the log in the configuration file.

The windows:windows configuration file is My.ini, usually under the MySQL installation directory or c:/windows.

The Linux:linux configuration file is my.cnf, usually under/etc.

Under Linux:

SQL code

# input in [mysqld]

#log

Log-error=/usr/local/mysql/log/error.log

Log=/usr/local/mysql/log/mysql.log

long_query_time=2

log-slow-queries=/usr/local/mysql/log/slowquery.log

[SQL]

# input in [mysqld]

#log

Log-error=/usr/local/mysql/log/error.log

Log=/usr/local/mysql/log/mysql.log

long_query_time=2

log-slow-queries=/usr/local/mysql/log/slowquery.log

Under Windows:

SQL code

# input in [mysqld]

#log

Log-error= "E:/progra~1/easyph~1.0b1/mysql/logs/error.log"

Log= "E:/progra~1/easyph~1.0b1/mysql/logs/mysql.log"

long_query_time=2

Log-slow-queries= "E:/progra~1/easyph~1.0b1/mysql/logs/slowquery.log"

[SQL]

# input in [mysqld]

#log

Log-error= "E:/progra~1/easyph~1.0b1/mysql/logs/error.log"

Log= "E:/progra~1/easyph~1.0b1/mysql/logs/mysql.log"

long_query_time=2

Log-slow-queries= "E:/progra~1/easyph~1.0b1/mysql/logs/slowquery.log"

Turn on Slow query

Long_query_time = 2--refers to the execution of more than how long SQL will be log down, here is 2 seconds

log-slow-queries=/usr/local/mysql/log/slowquery.log--Log the query back to a slower statement

Log-queries-not-using-indexes = nouseindex.log--literally, log down. Query with no index