Can a primary key of one table be a foreign key of another table? I am working on a scenario like this :
I have an employee table which has columns like this

Employee_ID
First_Name
Last_Name
Employee_Designation


Also I have a Joining_Vital table 

Employee_ID
Joining_ID
Joining_Date


How can I link this two tables ?
As I guess it would be a many-to-one relationship(as one joining_vital can contain many employees) from Employee table to  Joining_Vital table

I cannot establish the foreign key on the Employee_ID column of the Employee table.
I am naive to Database thing
Could you guys please help me out how to do it?
I cannot figure out the scenario
Please explain me out. Am I missing anything here?
Hi and welcome to the forums. A simple Google led me here.

CREATE TABLE employee
(
  Employee_ID INT,
  First_name VARCHAR(25),
  Last_name VARCHAR(25),
  PRIMARY KEY (Employee_ID),  -- Must be present - otherwise you cannot create the FOREIGN KEY
  Employee_designation VARCHAR(10)
);

CREATE TABLE joining_vital
(
  Employee_ID INT(10),
  Joining_ID INT(10),
  Joining_date DATE,
  FOREIGN KEY (Employee_ID) REFERENCES employee (Employee_ID)
);


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