This document discusses structured and unstructured data, with examples of each. It also defines key database concepts like fields, records, primary keys, and how relational databases split data across tables and link them together using foreign keys. Relational databases reduce data duplication by separating data into normalized tables that can be joined through common primary and foreign keys.

1. GCSE COMPUTER SCIENCE
Data
Databases

2. Structured & Unstructured Data
You need to be able to name some examples of structured and
unstructured data.
Presentations DocumentsPhotos Videos
Unstructured Data
Customer DetailsAddress Book Train Timetable
Structured Data
Databases are used to store structured data.

3. Key Terms
One piece of information.FIELD
All of the data or information about one item.RECORD
Student_ID First_Name Last_Name Address DOB Gender
1 John Curtis 12 Brook Lane 21/03/1990 Male
2 Ben Jackson 1 Totters Lane 15/04/1990 Male
3 Sarah Smith 60 Belsize Rd 6/06/1990 Female
A unique identifier for each record.PRIMARY KEY

4. Relational Databases
Relational databases split data across different tables to reduce
duplication.
A foreign key is used to link tables together and create a relationship
between them. It is a field in one table that is linked to the primary key
in another table.
Student_ID
First_Name
Last_Name
Address
DOB
Gender
Class_ID
Student_ID
Subject
Teacher_ID

5. One piece of information.FIELD
All of the data or information about one item.RECORD
A unique identifier for each record.
PRIMARY
KEY