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IB DP Computer Science — A3 Databases — Database design | SL | A3.2.4
📋 What You Will Learn
- Construct well-defined relational tables from a scenario, choosing sensible attributes and data types
- Define and correctly use primary keys, foreign keys, composite keys and concatenated keys
- Link tables to represent one-to-many and many-to-many relationships
- Write the tables as CREATE TABLE statements in SQL
- Explain how well-defined tables enforce entity, referential and domain integrity
🧩 Why This Matters A single giant spreadsheet of "everything" repeats the same student name on every row and breaks the moment someone changes their phone number in one place but not another. A relational database splits the data into small, single-purpose tables and then links them with keys — each fact is stored exactly once, and the links reassemble the full picture on demand.
Anatomy of a Relational Table
📖 Definition — Table (relation) A table is a named collection of related data organised into rows (records/tuples), each describing one instance of an