Database Management Systems (CP 224) โ Exam Mastery Roadmap
This roadmap will guide you step by step to master ADVANCED DBMS concepts very fast and pass exams with confidence, while also building skills that are directly useful in real world systems.
1. Data Modeling with EER (Enhanced Entity-Relationship) Diagrams
I. Core Concepts
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EER Basics : Entities, Attributes, Relationships : Extended Entity Relational Model, Make sure you understand it has added features you must know(eg generalization etc..)
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Constraints : Disjoint vs. Overlapping, Participation (Total/Partial) : Understand how these constraints are drawn on the EER and which symbols are used
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EER โ Relational Mapping : How to convert diagrams into normalized tables
Goal: Be able to draw clean EER diagrams and confidently map them into relational tables (This is a very common exam question).
2. Relational Database Design & Normalization
i. Core Concepts
Functional Dependencies (FDs) : Closure sets, Canonical covers
- Understand the meaning of functional dependency
- Know the types of functional dependency
- Understand Canonical cover and how to find it, from a set of functional dependencies
- The Closure sets, what are they?
Normal Forms : 1NF, 2NF, 3NF, BCNF (with anomalies explained)
- Be able to explain the conditions of all the normal forms
- Explain the anomalies that may oaccur in the databases
Decomposition : Dependency preservation and Lossless join
Exam Tip: Normalization is about spotting data anomalies. The more examples you practice, the faster you will recognize the patterns.
3. Relational Algebra & Query Optimization
i. Core Concepts
Basic Operations : SELECT (ฯ), PROJECT (ฯ), JOIN (โจ), UNION (โช), DIVISION (รท)
- Do much practice here, this question is in every exam
Advanced : Aggregate functions, GROUP BY
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Lean to use the agregate functions
SQL โ Algebra Translation : Converting queries into algebra expressions
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This question is in every Exam
ii. Practical Learning
- Convert at least 10 SQL queries into algebra (JOINs are exam favorite questions)
- Practice nested queries and multitable joins
Note: Relational algebra is the foundation of query optimization. If you can convert SQL to algebra, optimization questions become easy.
4. Transactions Concurrency Control
i. Core Concepts
ACID Properties : Atomicity, Consistency, Isolation, Durability
- Be able to explain the meaning of transaction
- And why the ACID properties are important
Schedules : Serial vs. Non-serial execution
- Must know the Types of schedules and why are they called so.
- Be able to perfrom questions dealing with these schedules ie identifying serial and non serial just by seeing.
Serializability : Conflict and View serializability (via precedence graphs)
- Learn the meaning of conflict and view serializability
- Lean how to prove if the schedules are conflict or view serializable
ii. Practical Learning
- Draw precedence graphs to test for serializability
- Identify recoverable vs. irrecoverable schedules
- Analyze sample problems step by step
Exam Focus: Graph based serializability questions are guaranteed in most DBMS exams.
5. Recovery and SQL Transactions
i. Core Concepts
- Recovery Mechanisms : Cascading rollbacks, Strict vs. Cascadeless schedules
- SQL TCL Commands : COMMIT, ROLLBACK, SAVEPOINT
- Isolation Levels : Read uncommitted, committed, repeatable, serializable
6. Object-Oriented Databases (OODBMS)
i. Core Concepts
- OO Principles in DB : Encapsulation, Inheritance, Object Identity
- ODMG Standards : Object Definition Language (ODL) basics
- OR Mapping : Mapping classes to relational tables
I have not seen these questions in the Exams
4 Hour Study Plan
- Hour1 โ EER + Relational Algebra
- Hour 2 โ Normalization + Functional Dependencies
- Hour 3 โ Transactions + Concurrency Control
- Hour 4 โ Recovery + OO Databases + Final Review
Exam Success Formula
i. High Marks Topics
- Normalization (1NF โ BCNF)
- Relational Algebra Queries
- Transaction Scheduling and Serializability
- EER Diagram Design and Mapping