Database Relationship between two or more tables in sql server

1^st step: Make new Database Diagram

2^nd step: Add required tables in diagram

3^rd step: Click on the Primary key Icon

4^th step: The relationship Icon is visible now

5^th step: Press the Left Key of Mouse/Touch pad on the relationship Icon and drag towards the other table drop at the field which you want to use as foreign key

6^th step: Tables and Columns Relationship window is visible, now click OK button

7^th step: Click on the Insert and Update Specification

8^th step: Change the Delete Rule to Cascade from No Action if and only if you want to delete foreign key record if primary key record is deleted

9^th step: Change the Update Rule to Cascade from No Action if and only if you want to update foreign key row if primary key row is updated

10^th step: Press OK button

11^th step: A connection is visible between two tables and save the diagram to effects on the tables by pressing CTRL+S