Relational database structure

This type of approach has no pointers and no hierarchy, instead the data are stored in simple records known as tuples. Tuples are sets of fields which each contain an attribute.

Tuples are grouped together in tables known as relations. Each table or relation is usually a separate file.

Data are extracted from a relational database by the user defining the relation that is appropriate to the query. Structured query language (SQL) is commonly used to query the database.