1、创建数据库指定数据库的字符集
mysql>create database mydb character set utf-8;
通过配置文件设置创建数据库时字符集:
#vi /var/lib/mysql/mydb/db.opt
default-character-set=latin1
default-collation=latin1_swedish_ci 为default-character-set=utf8
default-collation=utf8_general_ci
重起MySQL:
# /usr/share/mysql/mysqladmin –uroot –p shutdown
# /usr/share/mysql/bin/mysqld_safe &
2 、在已经存数据库的情况下,mysql命令行对指定的数据库进行修改数据库的字符集
MySQL>use mydb
mysql>alter database mydb character set utf-8;
3 、通过MySQL 命令行修改:
mysql> set character_set_client=utf8;
Query OK, 0 rows affected (0.00 sec)
mysql> set character_set_connection=utf8;
Query OK, 0 rows affected (0.00 sec)
mysql> set character_set_database=utf8;
Query OK, 0 rows affected (0.00 sec)
mysql> set character_set_results=utf8;
Query OK, 0 rows affected (0.00 sec)
mysql> set character_set_server=utf8;
Query OK, 0 rows affected (0.00 sec)
mysql> set character_set_system=utf8;
Query OK, 0 rows affected (0.01 sec)
mysql> set collation_connection=utf8;
Query OK, 0 rows affected (0.01 sec)
mysql> set collation_database=utf8;
Query OK, 0 rows affected (0.01 sec)
mysql> set collation_server=utf8;
Query OK, 0 rows affected (0.01 sec)
查看:
mysql> show variables like 'character_set_%';
+--------------------------+----------------------------+
| Variable_name | Value |
+--------------------------+----------------------------+
| character_set_client | utf8 |
| character_set_connection | utf8 |
| character_set_database | utf8 |
|character_set_filesystem|binary |
| character_set_results | utf8 |
| character_set_server | utf8 |
| character_set_system | utf8 |
| character_sets_dir | /usr/share/mysql/charsets/ |
+--------------------------+----------------------------+
8 rows in set (0.03 sec)
mysql> show variables like 'collation_%';
+----------------------+-----------------+
| Variable_name | Value |
+----------------------+-----------------+
| collation_connection | utf8_general_ci |
| collation_database | utf8_general_ci |
| collation_server | utf8_general_ci |
+----------------------+-----------------+
3 rows in set (0.04 sec)
-------------------------------------------------------------------------
查看三种MySQL字符集的方法mysql> show variables like '%char%';
+--------------------------+-------------------------------------+------
| Variable_name | Value |......
+--------------------------+-------------------------------------+------
| character_set_client | utf8 |...... -- 客户端字符集
| character_set_connection | utf8 |......
| character_set_database | utf8 |...... -- 数据库字符集
| character_set_filesystem | binary |......
| character_set_results | utf8 |......
| character_set_server | utf8 |...... -- 服务器字符集
| character_set_system | utf8 |......
| character_sets_dir | D:\MySQL Server 5.0\share\charsets\ |......
+--------------------------+-------------------------------------+------
二、查看MySQL数据表(table)的MySQL字符集。
mysql> show table status from sqlstudy_db like '%countries%';
+-----------+--------+---------+------------+------+-----------------+------
| Name | Engine | Version | Row_format | Rows | Collation |......
+-----------+--------+---------+------------+------+-----------------+------
| countries | InnoDB | 10 | Compact | 11 | utf8_general_ci |......
+-----------+--------+---------+------------+------+-----------------+------
三、查看MySQL数据列(column)的MySQL字符集。
mysql> show full columns from countries;
+----------------------+-------------+-----------------+--------
| Field | Type | Collation | .......
+----------------------+-------------+-----------------+--------
| countries_id | int(11) | NULL | .......
| countries_name | varchar(64) | utf8_general_ci | .......
| countries_iso_code_2 | char(2) | utf8_general_ci | .......
| countries_iso_code_3 | char(3) | utf8_general_ci | .......
| address_format_id | int(11) | NULL | .......
+----------------------+-------------+-----------------+--------
MYSQL 字符集问题
MySQL 的字符集支持(Character Set Support) 有两个方面:字符集(Character set) 和排序方式(Collation) 。
对于字符集的支持细化到四个层次:
服务器(server) ,数据库(database) ,数据表(table) 和连接(connection) 。
1.MySQL 默认字符集
MySQL 对于字符集的指定可以细化到一个数据库,一张表,一列,应该用什么字符集。
但是,传统的程序在创建数据库和数据表时并没有使用那么复杂的配置,它们用的是默认的配置,那么,默认的配置从何而来呢?
(1) 编译MySQL 时,指定了一个默认的字符集,这个字符集是 latin1 ;
(2) 安装MySQL 时,可以在配置文件 (my.ini) 中指定一个默认的的字符集,如果没指定,这个值继承自编译时指定的;
(3) 启动mysqld 时,可以在命令行参数中指定一个默认的的字符集,如果没指定,这个值继承自配置文件中的配置, 此时
character_set_server 被设定为这个默认的字符集;
(4) 当创建一个新的数据库时,除非明确指定,这个数据库的字符集被缺省设定为character_set_server ;
(5) 当选定了一个数据库时,character_set_database 被设定为这个数据库默认的字符集;
(6) 在这个数据库里创建一张表时,表默认的字符集被设定为 character_set_database ,也就是这个数据库默认的字符集;
(7) 当在表内设置一栏时,除非明确指定,否则此栏缺省的字符集就是表默认的字符集;
简单的总结一下,如果什么地方都不修改,那么所有的数据库的所有表的所有栏位的都用 latin1
存储,不过我们如果安装 MySQL ,一般都会选择多语言支持,也就是说,安装程序会自动在配置文件中把default_character_set 设置为 UTF-8 ,这保证了缺省情况下,所有的数据库的所有表的所有栏位的都用 UTF-8存储。
2. 查看默认字符集( 默认情况下,mysql 的字符集是latin1(ISO_8859_1) 通常,查看系统的字符集和排序方式的设定可以通过下面的两条命令: mysql> SHOW VARIABLES LIKE 'character%';
+--------------------------+---------------------------------+
| Variable_name | Value |
+--------------------------+---------------------------------+
| character_set_client | latin1 |
| character_set_connection | latin1 |
| character_set_database | latin1 |
| character_set_filesystem | binary |
| character_set_results | latin1 |
| character_set_server | latin1 |
| character_set_system | utf8 |
| character_sets_dir | D:"mysql-5.0.37"share"charsets" |
+--------------------------+---------------------------------+
mysql> SHOW VARIABLES LIKE 'collation_%';
+----------------------+-----------------+
| Variable_name | Value |
+----------------------+-----------------+
| collation_connection | utf8_general_ci |
| collation_database | utf8_general_ci |
| collation_server | utf8_general_ci |
+----------------------+-----------------+
3. 修改默认字符集
(1) 最简单的修改方法,就是修改mysql 的my.cnf 文件中的字符集键值,
如
[client]
default-character-set = utf8
[mysqld]
character_set_server = utf8
修改完后,重启mysql 的服务,service mysql restart
使用 mysql> SHOW VARIABLES LIKE 'character%'; 查看,发现数据库编码均已改成utf8
+--------------------------+---------------------------------+
| Variable_name | Value |
+--------------------------+---------------------------------+
| character_set_client | utf8 |