amazon.co.ukBoolean Logic and Relational Databases
A-Level Computer Science revision: Boolean Logic and Relational Databases. Learning objectives, key points, worked examples and practice questions across AQA, Edexcel, OCR, WJEC and CCEA.
📌 Key Points
Key Fact: Boolean laws: Identity, Null, Idempotent, Complement, Commutative, Associative, Distributive, De Morgan, Absorption
Key Fact: K-maps: 2-4 variables, groups of 1s (SOP) or 0s (POS); don't cares
Key Fact: Circuits: Half adder (XOR+AND), Full adder (2 half + OR), MUX (select), Decoder (binary->one-hot)
Key Fact: Flip-flops: SR (set/reset), D (data), JK (toggle); Registers: shift, storage; Counters: async/sync
Key Fact: ER: entities, attributes, relationships (1:1, 1:N, M:N), keys (PK, FK, CK)
Key Fact: Normalisation: 1NF (atomic), 2NF (no partial FD), 3NF (no transitive FD), BCNF (det⇒cand key)
Key Fact: SQL: SELECT...FROM...WHERE...GROUP BY...HAVING...ORDER BY; JOINs (INNER, LEFT, RIGHT, FULL)
Key Fact: Aggregation: COUNT, SUM, AVG, MIN, MAX; Subqueries; ACID: Atomicity, Consistency, Isolation, Durability
Key Fact: Concurrency: locks (shared/exclusive), deadlock, 2PL; Indexes: B-tree, hash; Query optimisation
🎯 Learning Objectives
- Construct and simplify Boolean expressions using laws (De Morgan, distribution, absorption)
- Design combinational logic circuits: adders, multiplexers, decoders
- Understand sequential logic: flip-flops (SR, D, JK), registers, counters
- Design relational databases: ER modelling, normalisation (1NF, 2NF, 3NF, BCNF)
- Write SQL: DDL (CREATE, ALTER), DML (SELECT, INSERT, UPDATE, DELETE), joins, aggregation
- Understand ACID properties, transactions, concurrency control, indexing
💡 Worked Example
Exam-Style Question
Question: Normalise to 3NF: Student(StudentID, Name, CourseID, CourseName, TutorID, TutorName)
Model Answer:
FDs: StudentID->Name, CourseID->CourseName, TutorID, TutorID->TutorName. 1NF: atomic. 2NF: remove partial FD (CourseID->CourseName). Course(CourseID, CourseName, TutorID), Tutor(TutorID, TutorName), Student(StudentID, Name, CourseID). 3NF: remove transitive FD (TutorID->TutorName). Already in 3NF
❓ Practice Questions
Model answers are being added progressively - questions marked ✗ don't have one yet. Cross-check with your teacher or the official mark scheme.
Questions:
- Simplify: A·(A+B) + A·B✗ answer coming soon
- Design full adder from half adders✗ answer coming soon
- Draw ER for library system✗ answer coming soon
- Write SQL: students with avg grade > 70✗ answer coming soon
- Explain ACID with examples✗ answer coming soon
🎬 Video Resources
- Boolean Logic and Relational Databases - Overview -- YouTube Search
- Boolean Logic and Relational Databases - Exam Questions -- YouTube Search
📄 Past Papers & Exam Resources
🔗 Further Reading & Resources
- Physics & Maths Tutor - Boolean Logic and Relational Databases -- Free notes, worksheets, and past paper questions by topic
- Dr Frost Maths - Boolean Logic and Relational Databases -- Free resources, slides, and interactive questions
- BBC Bitesize - Boolean Logic and Relational Databases -- BBC Bitesize revision resources