Question

嗨，我对多对多的关系有一个疑问。我有三个表Employee，Department和EDJoin表。这里EDJoin表包含Employee和Department表的id，我想加入这两个表来获取两个表数据。使用EDJoin表我将如何在这两个表之间建立连接，即Employee和Department。以下是Employee和Department表的列详细信息。雇员： EMPID 名字中间名字姓年龄

系： DepartmentID的 DEPARTMENTNAME

EDJoin： EMPID DepartmentID的

请告诉我这些故事的查询。如何为这三个表编写查询，以便我可以从Employee和Department表中获取数据。

谢谢＆amp;问候 Sailendra Narayan Jena

Answer 1

你去......

select *
from Employee a
inner join EDJoin b on a.empIDd = b.empId
inner join Department c on b.departmentId = c.departmentId

诺尔

Answer 2

SELECT * FROM Employee as a
INNER JOIN EdJoin as b ON a.Id = b.empId
INNER JOIN Deparment as c ON b.deptId = c.id;

如果要显示特定的列替换（*）恩。

SELECT firstName,MiddleName,LastName,age,DeparmentName 
FROM Employee as a
INNER JOIN EdJoin as b ON a.Id = b.empId
INNER JOIN Department as c ON b.deptId = c.id;

SQL Join相关查询

2 个答案: