为两个表中的一列定义外键 [英] Define a Foreign Key for one column in two Tables

问题描述

我想在两个表中为一列定义一个外键。



我在VWD 2010工作。



我尝试了SELECT * FROM Employees INNER JOIN Departments ON（Employees.DepartmentID = Departments.ID）;



这有用但我添加时 ADO.net实体数据模型它没有显示两个表之间的外键桥。



如何获得该桥？

解决方案

您需要对外键重点进行一些研究[ ^ ]

这样的东西可能有用

  ALTER   TABLE 员工
  ADD   CONSTRAINT  FK_Department  FOREIGN  < span class =code-keyword> KEY （DepartmentID）
  REFERENCES 部门（ID）; 

I want to define a Foreign Key for one column in two Tables.

I am working in VWD 2010.

I tried "SELECT * FROM Employees INNER JOIN Departments ON (Employees.DepartmentID = Departments.ID);

That worked but when I add "ADO.net Entity Data Model" it did not show the Foreign Key Bridge between the two tables.

How do I get that bridge?

解决方案

You need to do some research on Foreign Key Contraints[^]
Something like this might work

ALTER TABLE Employees
ADD CONSTRAINT FK_Department FOREIGN KEY (DepartmentID)
    REFERENCES Departments (ID) ;

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