MySQL数据库操作常用命令小结
创建数据库 最简单的方式: CREATE DATABASE my_db; 或者是: CREATE DATABASE IF NOT EXISTS my_db; 创建utf8编码的数据库: CREATE DATABASE IF NOT EXISTS my_db default character set utf8 COLLATE utf8_general_ci; 那么在这个数据库下创建的所有数据
创建数据库
最简单的方式:
CREATE DATABASE my_db;
或者是:
CREATE DATABASE IF NOT EXISTS my_db;
创建utf8编码的数据库:
CREATE DATABASE IF NOT EXISTS my_db default character set utf8 COLLATE utf8_general_ci;
那么在这个数据库下创建的所有数据表的默认字符集都会是utf8了,注意后面这句话 "COLLATE utf8_general_ci",大致意思是在排序时根据utf8变码格式来排序。
查看数据库列表:
show databases;
使用数据库:
use my_db;
查看数据库默认编码:
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 | /usr/local/mysql-5.5.28-linux2.6-i686/share/charsets/ |
+--------------------------+-------------------------------------------------------+
可以看到character_set_database是lantin1.
修改数据库编码:
alter database my_db character set latin1;
删除数据库:
drop database my_db;
或者是:
drop database IF EXISTS my_db;

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