Working with databases

This section describes how to create and work with a database. As you read this section, keep in mind the following simple concepts:

The databases that you can create (called relational databases) are a collection of tables, related by primary and foreign keys. These tables hold the information in a database, and the tables and keys together define the structure of the database. A database may be stored in one or more database files, on one or more devices.
A database file also contains the system tables, which hold the schema definition as you build your database.