Explain the concept of a relational database.
A relational database is a database where data is structured as a series of related tables or entities.
- A student timetable app - where each student has many lessons
- A booking system - where each booking has a single time but one person may have many bookings
Be able to define the terms:
- attribute
- primary key
- composite primary key
- foreign key
| Key term | Definition |
|---|---|
| Attribute | An attribute describes the facts, details or characteristics of an entity |
| Primary Key | An attribute that uniquely identifies a record |
| Composite Primary Key | A set of attributes which together uniquely identify a record |
| Foreign Key | An attribute of one table which is the primary key of another |