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HomeDatabaseMysql TutorialMySQL数据库操作常用命令小结

MySQL数据库操作常用命令小结

Jun 07, 2016 pm 04:27 PM
mysqlcreateOrderCommonly usedoperatedatabasemost

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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