慕课--《与MySQL的零距离接触》第一章 初涉MySQL
1-1 概述
MySQL是一个开源的关系型数据库管理系统,分为社区版和企业版。
1-2 安装与配置
本人下载安装5.5.60(64位)
1-3 启动与停止MySQL服务
方法一:图形化界面
方法二:命令行
1-4 MySQL登录与退出
1-5 修改MySQL提示符
MySQL提示符:
1-6 常用命令及语法规范
常用命令:
语法规范:
1-7 操作数据库
【说明:{}表示必选,[]表示可选,|表示二选一】
创建数据库:
查看当前服务器下的数据库列表:
修改数据库:
删除数据库:
//以下命令及显示均在windows cmd 命令行模式下
mysql> CREATE DATABASE t1; //创建数据库
Query OK, 1 row affected(0.00 sec) //创建成功
mysql> SHOW DATABASES; //查看当前服务器下的数据库
+-------------------- +
| Database |
+-------------------- +
| information_schema |
| mysql |
| performance_schema |
| t1 |
| test |
+-------------------- +
5 rows in set(0.00 sec) //可以看到t1存在,其余4个为默认自带的数据库
mysql> CREATE DATABASE t1; //创建已存在的数据库t1,会报错
ERROR 1007 (HY000) : Can't create database 't1'; database exists
mysql> CREATE DATABASE IF NOT EXISTS t1; //使用参数IF NOT EXISTS创建已存在的数据库,会出现警告
Query OK, 1 row affected, 1 warning(0.00 sec)
mysql> SHOW WARNINGS; //查看警告类型
+------ - +------ + -------------------------------------------- - +
| Level | Code | Message |
+------ - +------ + -------------------------------------------- - +
| Note | 1007 | Can't create database 't1'; database exists |
+ ------ - +------ + -------------------------------------------- - +
1 row in set(0.00 sec)
mysql> SHOW CREATE DATABASE t1; //查看数据库的编码方式,由于之前未设置,所以默认为utf8
+---------- + ------------------------------------------------------------ - +
| Database | Create Database |
+---------- + ------------------------------------------------------------ - +
| t1 | CREATE DATABASE `t1` /*!40100 DEFAULT CHARACTER SET utf8 */ |
+---------- + ------------------------------------------------------------ - +
1 row in set(0.00 sec)
mysql> CREATE DATABASE IF NOT EXISTS t2 CHARACTER SET gbk; //创建数据库t2并指定编码方式为gbk
Query OK, 1 row affected(0.00 sec)
mysql> SHOW CREATE DATABASE t2;
+---------- + ------------------------------------------------------------ +
| Database | Create Database |
+---------- + ------------------------------------------------------------ +
| t2 | CREATE DATABASE `t2` /*!40100 DEFAULT CHARACTER SET gbk */ |
+---------- + ------------------------------------------------------------ +
1 row in set(0.00 sec)
mysql> ALTER DATABASE t2 CHARACTER SET = utf8; //修改数据库t2的编码方式为utf8
Query OK, 1 row affected(0.00 sec)
mysql> SHOW CREATE DATABASE t2;
+---------- + ------------------------------------------------------------ - +
| Database | Create Database |
+---------- + ------------------------------------------------------------ - +
| t2 | CREATE DATABASE `t2` /*!40100 DEFAULT CHARACTER SET utf8 */ |
+---------- + ------------------------------------------------------------ - +
1 row in set(0.00 sec)
mysql> DROP DATABASE t1; //删除数据库t1
Query OK, 0 rows affected(0.07 sec)
mysql> SHOW DATABASES;
+-------------------- +
| Database |
+-------------------- +
| information_schema |
| mysql |
| performance_schema |
| t2 |
| test |
+-------------------- +
5 rows in set(0.00 sec)
mysql> DROP DATABASE t1; //不能重复删除
ERROR 1008 (HY000) : Can't drop database 't1'; database doesn't exist
mysql> DROP DATABASE IF EXISTS t1;
Query OK, 0 rows affected, 1 warning(0.00 sec)
mysql> SHOW WARNINGS;
+------ - +------ + -------------------------------------------------- +
| Level | Code | Message |
+------ - +------ + -------------------------------------------------- +
| Note | 1008 | Can't drop database 't1'; database doesn't exist |
+------ - +------ + -------------------------------------------------- +
1 row in set(0.00 sec)