ASA Getting Started
Databases and Applications
Relational database concepts
A relational database is a set of related tables. You use primary keys and foreign keys to describe relationships between the information in different tables. Primary keys identify each row in a table uniquely, and foreign keys define the relationships between rows in different tables.
Primary keys and foreign keys let you use relational databases to hold information in an efficient manner, without redundancy.
Tables have a primary key
Tables are related by foreign keys