Mysql character set viewing and setting
The character set problem of MySQL is mainly two concepts, one is Character Sets, the other is Collations, the former is character content and coding, and the latter is some rules for comparing the former. These two parameter sets can be specified at four levels: database instance, single database, table, column, and join.
one。 View MySQL database server
Mysql > show variables like'% char%'
Modify server character set
a. Temporary modification
Mysql > SET character_set_server=utf8
b. Permanent modification
Open / etc/mysql/my.cnf and add character-set-server=utf8 after [mysqld]
Note after modification: service mysql restart
two。 View database character set
Mysql > show variables like'% char%'
Modify database character set
a. Temporary change
Mysql > SET character_set_database=utf8
b. Permanent change
Just change the server level.
3. View the character set of the MySQL data Table (table)
Mysql > show table status from Database like'% countries%'
Modify table level
Mysql > ALTER TABLE table_name DEFAULT CHARSET utf8
four。 View the character set of the MySQL data column (column).
Mysql > show full columns from countries
Modify column
Mysql > ALTER TABLE tablename CHANGE colnum VARCHAR (20) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL
Fifth, change the connection character set
a. Temporary change: mysql > SET character_set_client
b. Permanent change: open / etc/mysql/my.cnf and add default-character-set=utf8 after [client]
Note that restart after modification: service mysql restart
six。 View the character sets supported by the currently installed MySQL.
Mysql > show charset
Mysql > show char set
Permanent change:
Modify my.ini (under windows) or / etc/my.cnf (under linux) through configuration file
Add the following respectively
[mysqld]
Character_server_set=utf8
[mysql]
Default-character-set=utf8
[mysql.server]
Default-character-set=utf8
[mysql_safe]
Default-character-set=utf8
[client]
Default-character-set=utf8
Restart the service: service mysqld restart
