Midterm Exam Prep

The Spring 2026 paper worked end-to-end — all four parts (concepts, relational algebra, ER diagram, SQL) with reveal-able solutions, diagrams, and a mnemonic for every topic.

Sections

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Exam Pattern & Cheat Sheet

How the 50-mark paper is built, the mark split, every mnemonic, and a one-page reference.

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Part 1 — Concepts (solved)

DB & DBMS definitions, examples, and the full DB-users → roles mapping.

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Part 2 — Languages & RA (solved)

DDL/DCL/DML/TCL table plus every Q4 join worked out with live result tables.

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Part 3 — ER Diagram (solved)

Key & attribute classification of the schema, plus the full detailed ER diagram.

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Part 4 — SQL (solved)

All eight SQL sub-questions, each with the query, the reasoning, and the common trap.

Quick summary

EXAM: CSE 303 · Full marks 50 · 1 hr 30 min · answer ALL · partial grading ON.

PART 1 (CLO1) — DB Concepts            20 marks
   Define DB & DBMS · relational/NoSQL/cloud examples · DB users → roles.
PART 2 (CLO2) — Languages & Rel. Algebra
   DDL/DCL/DML/TCL table · Cartesian product · inner/outer joins · select.
PART 3 (CLO3) — ER Diagram             11 marks
   Keys · attribute types · strong/weak entity · relationships · full ER diagram.
PART 4 (CLO6) — SQL                    ~20 marks
   CREATE + INSERT · ALTER add/rename · CASE update · SELECT · GROUP BY/HAVING
   · EXCEPT set op · COUNT per group.

MNEMONICS:  PISM (DB traits) · RI·IACS (file drawbacks) · σπ∪−×ρ (6 RA ops)
            PLV (abstraction) · Super ⊇ Candidate ⊇ Primary (keys).

STRATEGY: partial grading is ON — write SOMETHING for every part. Bank Part 1 +
the CREATE-TABLE marks first, then spend time on the RA tables and ER diagram.