1. 登陆与退出
（1） 登陆
mysql –u用户名–p密码
此命令密码是明文
mysql –u用户名–p
Enter Password
登陆的同时指明主机号：
mysql –h主机名–u用户名 –p密码
登陆的同时指明端口号
mysql –h主机名–u用户名 –p密码–P端口号（3306）
登陆的同时修改命令提示符：
mysql –h主机名–u用户名 –p密码–P端口号（3306）--prompt=
命令提示符包括：
\u当前用户名
\h当前主机名
\D当前日期时间
\d当前打开的数据库
也可以在登陆后，修改命令提示符：
Promptkaikeba>
命令提示符改为kaikeba>
登陆的同时修改命令分隔符：
mysql –h主机名–u用户名 –p密码–P端口号（3306）--prompt= --delimiter=
也可以再登陆之后修改命令分隔符
Delimiter @
命令结束符变为：@
在登陆的同时打开数据库：
Mysql -u用户名 -p密码 -h主机名 -D数据库名
Eg:
Mysql -uroot-proot -hlocalhost -Dtest;
（2） 退出
Exit
\q
Quit
Ctrl+C快捷键
（3） SQL规范
数据库名、表名小写；关键字、保留字、函数名称大写；
SQL命令支持折行操作，但不能将单词、名称、或成对引号折行写
当名称与保留字冲突时，需用‘’括上名称
（4） 开启输出日志的形式
\T 文件保存位置及文件名称
\t 结束输出日志
按上下键调查之前写过的命令
2. DDL操作
（1） 创建数据库
CREATE{DATABASE|SCHEMA} db_name;
CREATE{DATABASE|SCHEMA} [IF NOT EXISTS] db_name;
CREATE{DATABASE|SCHEMA} [IF NOT EXISTS] db_name [[DEFAULT] CHARACTER SET [=] 字符集];
（2） 查看当前服务器下已有的数据库
SHOW{DATABASES|SCHEMA};
（3） 查看上一步操作得到的警告
SHOW WARNINGS
（4） 查看已创建数据库的编码方式
SHOW CREATEDATABASE db_name;
综合案例1：
mysql> CREATEDATABASE randongmei;
Query OK, 1 rowaffected (0.00 sec)
mysql> SHOWDATABASES;
+--------------------+
| Database |
+--------------------+
|information_schema |
| mysql |
|performance_schema |
|randongmei |
| test |
+--------------------+
5 rows in set(0.00 sec)
mysql> CREATESCHEMA king;
Query OK, 1 rowaffected (0.00 sec)
mysql> SHOWSCHEMAS;
+--------------------+
| Database |
+--------------------+
|information_schema |
| king |
| mysql |
| performance_schema|
|randongmei |
| test |
+--------------------+
6 rows in set(0.00 sec)
mysql> CREATESCHEMA king;
ERROR 1007(HY000): Can‘t create database ‘king‘; database exists
mysql> CREATESCHEMA IF NOT EXISTS king;
Query OK, 1 rowaffected, 1 warning (0.00 sec)
mysql> SHOWWARNINGS;
+-------+------+-----------------------------------------------+
| Level | Code |Message |
+-------+------+-----------------------------------------------+
| Note | 1007 | Can‘t create database ‘king‘;database exists |
+-------+------+-----------------------------------------------+
1 row in set(0.00 sec)
mysql> SHOWDATABASES;
+--------------------+
| Database |
+--------------------+
| information_schema|
| king |
| mysql |
|performance_schema |
|randongmei |
| test |
+--------------------+
6 rows in set(0.00 sec)
mysql> SHOWCREATE DATABASE randongmei;
+------------+---------------------------------------------------------------------+
| Database | Create Database |
+------------+---------------------------------------------------------------------+
| randongmei |CREATE DATABASE `randongmei` /*!40100 DEFAULT CHARACTER SET utf8 */ |
+------------+---------------------------------------------------------------------+
1 row in set(0.00 sec)
mysql> CREATEDATABASE IF NOT EXISTS test1 DEFAULT CHARACTER SET =‘gbk‘;
Query OK, 1 rowaffected (0.00 sec)
mysql> SHOWCREATE DATABASE test1
-> ;
+----------+---------------------------------------------------------------+
| Database |Create Database |
+----------+---------------------------------------------------------------+
| test1 | CREATE DATABASE `test1` /*!40100 DEFAULTCHARACTER SET gbk */ |
+----------+---------------------------------------------------------------+
1 row in set(0.00 sec)
mysql> CREATESCHEMA IF NOT EXISTS test3 CHARACTER SET ‘GBK‘;
Query OK, 1 rowaffected (0.00 sec)
mysql> \t
（5） 修改数据库的编码方式
ALTER{DATABASE|SCHEMA} db_name [[DEFAULT] CHARACTER SET [=] 字符集];
mysql> SHOWDATABASES;
+--------------------+
| Database |
+--------------------+
|information_schema |
| king |
| mysql |
|performance_schema |
|randongmei |
| test |
| test1 |
| test3 |
+--------------------+
8 rows in set(0.02 sec)
mysql> SHOWCREATE DATABASE test1;
+----------+---------------------------------------------------------------+
| Database |Create Database |
+----------+---------------------------------------------------------------+
| test1 | CREATE DATABASE `test1` /*!40100 DEFAULTCHARACTER SET gbk */ |
+----------+---------------------------------------------------------------+
1 row in set(0.00 sec)
mysql> ALTERDATABASE test1 DEFAULT CHARACTER SET ‘UTF8‘;
Query OK, 1 rowaffected (0.00 sec)
mysql> SHOWCREATE DATABASE test1;
+----------+----------------------------------------------------------------+
| Database |Create Database |
+----------+----------------------------------------------------------------+
| test1 |CREATE DATABASE `test1` /*!40100 DEFAULT CHARACTER SET utf8 */ |
+----------+----------------------------------------------------------------+
1 row in set(0.00 sec)
mysql> SHOWCREATE SCHEMA test3;
+----------+---------------------------------------------------------------+
| Database |Create Database |
+----------+---------------------------------------------------------------+
| test3 | CREATE DATABASE `test3` /*!40100 DEFAULTCHARACTER SET gbk */ |
+----------+---------------------------------------------------------------+
1 row in set(0.00 sec)
mysql> ALTERDATABASE test3 CHARACTER SET ‘UTF8‘;
Query OK, 1 rowaffected (0.00 sec)
mysql> SHOWCREATE DATABASE test3;
+----------+----------------------------------------------------------------+
| Database |Create Database |
+----------+----------------------------------------------------------------+
| test3 | CREATE DATABASE `test3` /*!40100 DEFAULTCHARACTER SET utf8 */ |
+----------+----------------------------------------------------------------+
1 row in set(0.00 sec)
mysql> \t
（6） 打开指定数据库
USE db_name;
（7） 得到当前已经打开的数据库
SELECT{DATABASE()|SCHEMA()};
mysql> SHOWDATABASES;
+--------------------+
| Database |
+--------------------+
|information_schema |
| king |
| mysql |
|performance_schema |
|randongmei |
| test |
| test1 |
| test3 |
+--------------------+
8 rows in set(0.00 sec)
mysql> USEtest1;
Database changed
mysql> SELECTDATABASE();
+------------+
| DATABASE() |
+------------+
| test1 |
+------------+
1 row in set(0.00 sec)
mysql> USErandongmei;
Database changed
mysql> SELECTSCHEMA();
+------------+
| SCHEMA() |
+------------+
| randongmei |
+------------+
1 row in set(0.00 sec)
mysql> \t
（8） 删除指定的数据库
DROP {DATABASE|SCHEMA} db_name;
DROP {DATABASE|SCHEMA} [IF EXISTS] db_name;
不可以一次删除多个数据库