2、创建名称为rewin的数据库
CREATE DATABASE rewin;

3、删除名称为rewin的数据库
DROP DATABASE rewin;

4、选择rewin数据库
USE rewin;

三、表操作SQL语句（登录之后必须用以上的USE命令选择一个数据库，再进行表操作）
1、显示当前数据库中存在什么表
SHOW TABLES;

2、创建数据库表zhangyan：在mysql>后粘贴以下SQL语句，存储引擎为MYISAM，字段id为主键、唯一索引。
CREATE TABLE `zhangyan` (
`id` INT( 5 ) UNSIGNED NOT NULL AUTO_INCREMENT ,
`username` VARCHAR( 20 ) NOT NULL ,
`password` CHAR( 32 ) NOT NULL ,
`time` DATETIME NOT NULL ,
`number` FLOAT( 10 ) NOT NULL ,
`content` TEXT NOT NULL ,
PRIMARY KEY ( `id` )
) ENGINE = MYISAM ;

3、查看zhangyan表结构
DESCRIBE zhangyan;

4、从表中检索信息
4.1、从zhangyan表中检索所有记录
SELECT * FROM zhangyan;

4.2、从zhangyan表中检索特定的行：字段username等于abc，字段number等于1，按字段id降序排列
SELECT * FROM zhangyan WHERE username = 'abc' AND number='1' ORDER BY id DESC;

4.3、从zhangyan表中检索指定的字段：username和password
SELECT username, password FROM zhangyan;

4.4、从zhangyan表中检索出唯一的不重复记录：
SELECT DISTINCT username FROM zhangyan;

5、插入信息到zhangyan表
INSERT INTO zhangyan (id, username, password, time, number, content) VALUES ('', 'abc', '123456', '2007-08-06 14:32:12', '23.41', 'hello world');

6、更新zhangyan表中的指定信息
UPDATE zhangyan SET content = 'hello china' WHERE username = 'abc';

7、删除zhangyan表中的指定信息
DELETE FROM zhangyan WHERE id = 1;

8、清空zhangyan表
DELETE FROM zhangyan;

9、删除zhangyan表
DROP TABLE zhangyan;

10、更改表结构，将zhangyan表username字段的字段类型改为CHAR(25)
ALTER TABLE zhangyan CHANGE username username CHAR(25);

11、将当前目录下的mysql.sql导入数据库
SOURCE ./mysql.sql;

四、数据库权限操作SQL语句
1、创建一个具有root权限，可从任何IP登录的用户sina，密码为zhangyan
GRANT ALL PRIVILEGES ON *.* TO 'sina'@'%' IDENTIFIED BY 'zhangyan' WITH GRANT OPTION;
FLUSH PRIVILEGES;

2、创建一个具有“数据操作”、“结构操作”权限，只能从192.168.1.***登录的用户sina，密码为zhangyan
GRANT SELECT , INSERT , UPDATE , DELETE , FILE , CREATE , DROP , INDEX , ALTER , CREATE TEMPORARY TABLES , CREATE VIEW , SHOW VIEW , CREATE ROUTINE, ALTER ROUTINE, EXECUTE ON *.* TO 'sina'@'192.168.1.%' IDENTIFIED BY 'zhangyan';

3、创建一个只拥有“数据操作”权限，只能从192.168.1.24登录，只能操作rewin数据库的zhangyan表的用户sina，密码为zhangyan
GRANT SELECT , INSERT , UPDATE , DELETE ON rewin.zhangyan TO 'sina'@'192.168.1.24' IDENTIFIED BY 'zhangyan';

4、创建一个拥有“数据操作”、“结构操作”权限，可从任何IP登录，只能操作rewin数据库的用户sina，密码为zhangyan
GRANT SELECT , INSERT , UPDATE , DELETE , CREATE , DROP , INDEX , ALTER , CREATE TEMPORARY TABLES , CREATE VIEW , SHOW VIEW , CREATE ROUTINE, ALTER ROUTINE, EXECUTE ON rewin.* TO 'sina'@'%' IDENTIFIED BY 'zhangyan';

5、删除用户
DROP USER 'sina'@'%';