mysql——多表——内连接查询

内连接查询：可以查询两个或者两个以上的表，当两个表中存在表示相同意义的字段时，可以通过该字段来连接这两个表；

当该字段的值相等时，就查询出该记录。

前期准备两个表：

create table employee ( num int(50),
                        d_id int(50),
                        name varchar(50),
                        age int(50),
                        sex varchar(50),
                        homeadd varchar(50)
                       );
 
insert into employee values(1,1001,'zhangsan',26,'nan','beijing');
insert into employee values(2,1001,'lisi',24,'nv','hunan');
insert into employee values(3,1002,'wangwu',25,'nan','jiangsu');
insert into employee values(4,1004,'aric',15,'nan','yingguo');
 
select * from employee;
 
create table department ( d_id int(50),
                          d_name varchar(50),
                          functione varchar(50),
                          address varchar(50)
                        );
 
insert into department values(1001,'keyanbu','yanfachanpin','3lou5hao');
insert into department values(1002,'shengchanbu','shengchanchanp','5louyiceng');
insert into department values(1003,'xiaoshoubu','cehuaxiaoshou','1louxiaoshoudating');
 
select * from department;

执行查询：

select num,name,employee.d_id,age,sex,d_name,functione from employee,department where employee.d_id = department.d_id;