mysql基本语法
建库建表Demo
-- 建库 create DATABASE db_book; use db_book; -- 建表 CREATE TABLE t_bookType( id int primary key auto_increment, bookTypeName varchar(20), bookTypeDesc varchar(200) ); CREATE TABLE t_book( id int primary key auto_increment, bookName varchar(20), author varchar(10), price decimal(6,2), bookTypeId int, constraint `fk` foreign key (`bookTypeId`) references `t_bookType`(`id`) ); -- 查看表结构 desc t_bookType; -- 查看表ddl(建表语句) show create table t_bookType; -- 重命名表 alter table t_book rename t_book2;
建立单表
-- 建表 create table `t_student` ( `id` double , `stuName` varchar (60), `age` double , `sex` varchar (30), `gradeName` varchar (60) ); -- 插入记录 insert into `t_student` (`id`, `stuName`, `age`, `sex`, `gradeName`) values('1','张一','23','男','一年级'); insert into `t_student` (`id`, `stuName`, `age`, `sex`, `gradeName`) values('2','张二','25','男','二年级'); insert into `t_student` (`id`, `stuName`, `age`, `sex`, `gradeName`) values('3','张三','23','男','一年级'); insert into `t_student` (`id`, `stuName`, `age`, `sex`, `gradeName`) values('4','张四','22','男','三年级'); insert into `t_student` (`id`, `stuName`, `age`, `sex`, `gradeName`) values('5','张五','21','女','一年级'); insert into `t_student` (`id`, `stuName`, `age`, `sex`, `gradeName`) values('6','李一','26','女','二年级'); insert into `t_student` (`id`, `stuName`, `age`, `sex`, `gradeName`) values('7','李二','20','男','三年级'); insert into `t_student` (`id`, `stuName`, `age`, `sex`, `gradeName`) values('8','李三','21','女','二年级'); insert into `t_student` (`id`, `stuName`, `age`, `sex`, `gradeName`) values('9','李四','22','男','一年级'); insert into `t_student` (`id`, `stuName`, `age`, `sex`, `gradeName`) values('10','李五','25','男','二年级'); insert into `t_student` (`id`, `stuName`, `age`, `sex`, `gradeName`) values('11','小黑','21',NULL,'二年级'); insert into `t_student` (`id`, `stuName`, `age`, `sex`, `gradeName`) values('12','小白','23','男','二年级'); insert into `t_student` (`id`, `stuName`, `age`, `sex`, `gradeName`) values('13','小红','24',NULL,'二年级');