CentOS of MySQL command

1.本地连接数据库

[root@iZ253lxv4i0Z mysql]# mysql -u root -p
Enter password:

or:

[root@iZ253lxv4i0Z mysql]# mysql -u root -p mysql
Enter password:

2.查看端口

mysql> show global variables like 'port'
-> ;
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| port | 3306 |
+---------------+-------+

3.查看数据库

mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| test |
| wordpress_db |
+--------------------+

4.show variables like 'collation_%';

+----------------------+-------------------+
| Variable_name | Value |
+----------------------+-------------------+
| collation_connection | utf8_general_ci |
| collation_database | latin1_swedish_ci |
| collation_server | latin1_swedish_ci |
+----------------------+-------------------+

 5.show variables like 'character_set_%';

+--------------------------+----------------------------------------------+
| Variable_name | Value |
+--------------------------+----------------------------------------------+
| character_set_client | utf8 |
| character_set_connection | utf8 |
| character_set_database | latin1 |
| character_set_filesystem | binary |
| character_set_results | utf8 |
| character_set_server | latin1 |
| character_set_system | utf8 |
| character_sets_dir | /alidata/server/mysql-5.6.15/share/charsets/ |
+--------------------------+----------------------------------------------+

6.alter database mydb character set utf-8;

ERROR 1115 (42000): Unknown character set: 'utf'

7.alter database mydb character set utf8;

ERROR 1 (HY000): Can't create/write to file './mydb/db.opt' (Errcode: 2 - No such file or directory)

8.quit;

退出

9.通过配置文件修改:

　　修改/var/lib/mysql/mydb/db.opt(进入mysql根目录，找到data目录并cd进入，再找到你要修改的数据库的目录并进入，进去之后就可以看到db.opt)
　　default-character-set=latin1
　　default-collation=latin1_swedish_ci
　　为
　　default-character-set=utf8
　　default-collation=utf8_general_ci

10.重启MySQL(进入Server目录)

　　service mysqld restart

11.启动/停止MySQL(进入Server目录)

　　service mysqld start

　　service mysqld stop

12.