AQA GCSE · Question 18.2 · Relational databases and structured query language (SQL)
State one benefit of using relational databases.
How to approach this question
Think about why data is split into multiple tables instead of being kept in one large table. What problem does this solve? Consider what would happen in the `Award` table if you had to re-type the member's full name and join date for every single award they received.
Full Answer
They reduce data redundancy.
One of the main benefits of using a relational database is the **reduction of data redundancy**. Redundancy is when the same piece of data is stored in multiple places. In a non-relational (flat-file) system, you might store a member's full name and join date with every award they receive. If a member receives 10 awards, their name would be stored 10 times. In a relational database, the member's details are stored only once in the `Member` table. The `Award` table simply references the member using their `MemberID`. This saves space and, more importantly, improves data consistency. If a member's name needs to be updated, it only has to be changed in one place.
Common mistakes
✗ Stating a feature (e.g., "it uses tables") instead of a benefit.
✗ Vague answers like "it's more organised".
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