Establishing Solid Relationships

In Chapter 1, you learned that a relationship exists between a pair of tables if records in the first table are in some way associated with records in the second table. You also learned that the relationship itself can be designated as one of three types: one-to-one, one-to-many, and many-to-many. And you learned that each type of relationship is established in a specific manner. Let’s review this for a moment.


The diagram symbols shown in this section are part of the diagramming method presented in Mike Hernandez’s book Database Design for Mere Mortals (Addison-Wesley, 2004). PK indicates a primary key field. FK indicates a foreign key field. CPK indicates a field that is part of a composite primary key. ...

Get SQL Queries for Mere Mortals: A Hands-On Guide to Data Manipulation in SQL, Second Edition now with O’Reilly online learning.

O’Reilly members experience live online training, plus books, videos, and digital content from 200+ publishers.