Can a primary key of one table be a foreign key of another table?
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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