Data & representation · Both
Databases & SQL Basics
Databases organise data so it can be stored, searched and updated efficiently.
Structure
• **Table** – collection of related data
• **Record** – one row (one item)
• **Field** – one column (one attribute)
• **Primary key** – unique identifier for each record
SQL and validation
Simple query pattern:
SELECT fields FROM table WHERE condition
Validation checks data on entry (range, type, presence, format) to reduce errors.
Worked example
SQL to get all pupils in Year 11?
Solution: SELECT * FROM Pupils WHERE Year = 11
Practice questions
1. What is a primary key?
2. Name two validation checks.