【MySQL】(1)初涉MySQL_MySQL
1. MySQL目录结构
bin:存储可执行文件
data:存储数据文件
docs:文档
include:存储包含的头文件
lib:存储库文件
share:错误消息和字符集文件
注意:这里是utf8而不是utf-8
2. 修改编码方式
一般需要修改MySQL安装目录下的my.ini配置文件中:
[mysql]
default-character-set=utf8
[mysqld]
character-set-server=utf8
3. 启动/关闭MySQL服务
(1). 可以使用windows--->服务--->MySQL服务--->启动/停止
(2). 使用命令行net start mysql启动服务、使用net stop mysql停止服务
4. 登录与退出
一些MySQL命令:
将bin路径添加到系统环境变量中,打开命令提示行:
登录:mysql -uroot -p -P3306 -h126.0.0.1,然后输入密码即可实现登录
退出:quit或者exit或者\q
5. 修改MySQL提示符
使用:mysql -uroot -proot --prompt 提示符登录后可以使用:prompt 提示符
几种可以设置的特殊提示符:
\D:完整的日期
\d:当前数据库
\h:服务器名称
\u:当前用户
6. MySQL常用命令及语法规范
SELECT VERSION(); 显示当前服务器版本
SELECT NOW(); 显示当前日期时间
SELECT USER(); 显示当前用户
(1). 关键字与函数名称全部大写
(2). 数据库名称、表名称、字段名称全部小写
(3). SQL语句必须以分号结束
7. 操作数据库
创建数据库:CREATE {DATABASE | SCHEMA} [IF NOT EXISTS] db_name [DEFAULT] CHARACTER SET [=] charset_name;查看当前服务器下的数据表列表:SHOW {DATABASES | SCHEMA} [LIKE 'pattern' | WHERE expr];
查看警告信息:SHOW WARNINGS;
查看创建信息:SHOW CREATE DATABASE db; (查看创建db数据库的语句)
使用gbk编码创建数据库:CREATE DATABASE IF NOT EXISTS db2 CHARACTER SET gbk;
修改数据库:ALTER {DATABASE | SCHEMA} [db_name] [DEFAULT] CHARACTER SET [=] charset_name;
删除数据库:DROP {DATABASE | SCHEMA} [IF EXISTS] db_name;

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