Relational databases have only one type of data container: the table. When designing any database, the main concern is defining the tables that make up the database and defining how those tables reference and interact with each other.

Designing tables for a database is a lot like designing classes or data structures for an application. Simple designs are largely driven by common sense, but as things get larger and more complex, it takes some experience and insight to keep the design clean and on target. Understanding basic design principles and standard approaches can be a big help.