MySQL——基础——内连接

一、内连接查询语法

隐式内连接

SELECT 字段列表 FROM 表1，表2 WHERE 条件...;

显示内连接

SELECT 字段列表 FROM 表1 [INNER] JOIN 表2 ON 连接条件...;

内连接查询的是两张表交集的部分

二、内连接演示

1.查询每一个员工的姓名，及关联的部门的名称(隐式内连接实现)
表结构：participators,department
连接条件：participators.dept_id = department.id

select participators.name, department.name
from participators,
department
where participators.dept_id = department.id
order by participators.id;

select p.name, d.name
from participators p,  # 起别名
department d
where p.dept_id = d.id
order by p.id;

2.查询每一个员工的姓名，及关联的部门的名称(显式内连接实现) --- INNER JOIN ... ON ...

表结构：participators,department
连接条件：participators.dept_id = department.id

select p.name, d.name
from participators p
inner join department d on p.dept_id = d.id
order by p.id;

select p.name, d.name
from participators p
join department d on p.dept_id = d.id
order by p.id;

# inner可省略