Database Schema

Nota:

•   šThis is a complete logical view of the database.   

1. All tables

   Nota:

   • Relations - All relations are tables but not all tables are relations.
2. Columns in each table
3. Primary Key of Each table

   Nota:

   • Primary Key values must be unique in every row. Also known as the Entity Integrity Constraint
4. Foreign Keys that link the tables together

   Nota:

   • Foreign Key - šA column or composite of columns that is the primary key of a table other than the one in which it appears.