谁能帮我解释下面这段代码啊?(包括怎么用)

来源:百度知道 编辑:UC知道 时间:2024/06/04 06:47:43
-------------sql文件------------------

create database vote

use vote

create table votemaster
(
voteid int primary key,--投票编号
votetitle varchar(100) not null,--投票标题
votesum int default 0 --投票的总票数
)

insert into votemaster values(1,'书记选举',0)
insert into votemaster values(2,'市长选举',0)

select * from votemaster

create table vote
(
voteid int foreign key references votemaster(voteid),--该键是主表的联系键
id int not null,
voteitem varchar(20) not null,
votenun int default 0,
)

insert into vote values(1,1,'张三',0)
insert into vote values(1,2,'李达',0)
insert into vote values(1,3,'钟馗',0)
insert into vote values(1,4,'江尚',0)
insert into vote values(2,1,'刘文采',0)
insert into vote values(2,2,'李世民',0)
insert into vote values(2,3,'周正',0)
insert into vote values(2,4,'张三疯

create database vote '创建数据库VOTE

use vote

create table votemaster ‘创建表VOTEMASTER
(
voteid int primary key,--投票编号 '表中关键字段
votetitle varchar(100) not null,--投票标题 ’字段类型不为空
votesum int default 0 --投票的总票数
)

insert into votemaster values(1,'书记选举',0) ‘向表中插入数据
insert into votemaster values(2,'市长选举',0)

select * from votemaster ’下面的意思也一样

create table vote
(
voteid int foreign key references votemaster(voteid),--该键是主表的联系键
id int not null,
voteitem varchar(20) not null,
votenun int default 0,
)

insert into vote values(1,1,'张三',0)
insert into vote values(1,2,'李达',0)
insert into vote values(1,3,'钟馗',0)
insert into vote values(1,4,'江尚',0)
insert into vote values(2,1,'刘文采',0)
insert into vote values(2,2,'李世民',0)
insert into vote values(2,3,'周正',0) <