Summary AQA GCSE Computer Science Revision Notes - 3.7 Relational databases and structured query language (SQL)

3.7.1 Relational Databases
Data vs Information
GiGo
How to store data
What is a database?
Advantages of Structured Storage
How to make a database
Database Schema
Parts of a database
Primary key
Foreign key
Advantages of Foreign Keys
Two types of database
Flat file
Relational database
Database Schema
Summary




Data vs Information
Information is data with context



Data is valuable

monetary value

personal value



Data must have

integrity

accuracy

reliability




3.7.1 Relational Databases 1

, GiGo

GIGO - Garbage In Garbage Out (if you collect useless information in your database or don’t
verify email addresses and phone numbers your database will be useless)




How to store data

Structured Unstructured

Contacts in phone Photos/Video

School timetable Documents

Product catalogue Music/Audio




What is a database?

A database is a structured collection of data that allows users to extract information quickly and efficiently.




Advantages of Structured Storage
Easier to find information

Easier to add data

Easier to update already existing data

Easier to delete data

Easier to maintain integrity




💡 Only structured data can be stored in a database




How to make a database
Data is stored in tables

Columns are fields

Rows are records




3.7.1 Relational Databases 2