MySQL Tipps und Tricks: Difference between revisions

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Line 28: Line 28:
mysql> SET GLOBAL general_log = 'ON';
mysql> SET GLOBAL general_log = 'ON';
Query OK, 0 rows affected (0.00 sec)
Query OK, 0 rows affected (0.00 sec)
</source>


<source lang=mysql>
mysql> SET GLOBAL general_log = 'OFF';
mysql> SET GLOBAL general_log = 'OFF';
Query OK, 0 rows affected (0.00 sec)
</source>
===Enable/disable general logging===
<source lang=mysql>
mysql> SET GLOBAL slow_query_log_file = '/var/lib/mysql/general.log';
Query OK, 0 rows affected (0.00 sec)
mysql> SET GLOBAL slow_query_log = 'ON';
Query OK, 0 rows affected (0.00 sec)
</source>
<source lang=mysql>
mysql> SET GLOBAL slow_query_log = 'OFF';
Query OK, 0 rows affected (0.00 sec)
Query OK, 0 rows affected (0.00 sec)
</source>
</source>

Revision as of 11:33, 12 August 2015

Tipps und Tricks


Oneliner

All grants

# mysql --skip-column-names --batch --execute 'select concat_ws("@",user,host) from mysql.user' | xargs -n 1 -i mysql --execute 'show grants for {}'

InnoDB space

Per database

mysql> select table_schema as database_name, sum(round(data_length/1024/1024,2)) as total_size_mb from information_schema.tables where engine like 'innodb' group by table_schema order by total_size_mb;

Per table

mysql> select table_schema as database_name,table_name,round(data_length/1024/1024,2) as size_mb from information_schema.tables order by size_mb;

Logging

Enable/disable general logging

mysql> SET GLOBAL general_log_file = '/var/lib/mysql/general.log';
Query OK, 0 rows affected (0.00 sec)

mysql> SET GLOBAL general_log = 'ON';
Query OK, 0 rows affected (0.00 sec)
mysql> SET GLOBAL general_log = 'OFF';
Query OK, 0 rows affected (0.00 sec)

Enable/disable general logging

mysql> SET GLOBAL slow_query_log_file = '/var/lib/mysql/general.log';
Query OK, 0 rows affected (0.00 sec)

mysql> SET GLOBAL slow_query_log = 'ON';
Query OK, 0 rows affected (0.00 sec)
mysql> SET GLOBAL slow_query_log = 'OFF';
Query OK, 0 rows affected (0.00 sec)