mysql base

--启动mysql服务器net start mysqlmysql  -uroot -p--查看数据库show databases--创建新的数据库create database dbname charset utf8;--进入数据库use dbname--建立表格--班级表：create table class(class_id int ,        class_name varchar(10) not null,        class_num int not null,        class_desc varchar(50),       primary key(class_id))engine=innodb default charset=gbk; --学生表：create table students(        s_id int primary key,        s_name varchar(20) not null,        s_sex char(2) default '男',        s_age tinyint not null,        s_desc varchar(50),        class_id int not null)engine=innodb default charset=gbk; --添加外键：alter table students add constraint students_ca_FK foreign key(class_id) references class(class_id); --删除数据DELETE FROM `student` WHERE `student`.`StuNo` = '13101';-- 更新记录UPDATE `student` SET `StuName` = '张月', `Sex` = '女' WHERE `student`.`StuNo` = '13101';-- 修改表结构--增加列：alter table student add Age int(2);--删除列alter table student drop Age;--修改列名alter table student change Age StuAge int(2);--修改表名alter table student rename stu;--删除表格drop table Student;--删除数据库drop database dbname;--添加用户grant all privileges on *.* to user @ "%" indentified  by "123456";--修改密码  --mysql/bin mysqladmin  -uroot password 123456--orset password for user=password("123456");--撤销用户权限revoke all on "." from user @"%";--删除用户use mysql;delete from user where user="user"