01. PROJECT_MANIFEST
McDonald's App — DB Reverse Engineering
Reverse-engineered the McDonald's ordering app's data layer: mapped entities, drew the ERD, wrote the DDL, and authored twelve production-style SQL queries covering orders, menu items, and transactions.
ROLE
Database Engineer (team of 3)
TIMELINE
Semester 4
STATUS
COMPLETED
01. OVERVIEW
Working with two teammates, I helped reverse-engineer the data model behind a McDonald's-style ordering app — starting from app behavior and screens, then working backward to a normalized relational schema.
The output was a full makalah (academic paper) and presentation covering the ERD, DDL statements, and twelve SQL queries handling common operations: order history, menu availability, and revenue-style aggregations.
02. CORE_CHALLENGES
// 01_ERD
Inferring entity relationships (orders, items, branches, customers) purely from app UI and flow, without direct schema access.
// 02_NORM
Keeping the schema normalized while still matching real-world ordering behavior, like combo items and modifiers.
// 03_TEAM
Splitting slide and section ownership across three people while keeping the ERD and DDL internally consistent.
03. SYSTEM_OUTPUT
ENTITIES_MAPPED
9
SQL_QUERIES
12
TEAM_SIZE
3
/* ARCHITECTURE_LOG_0x44 */
“The hardest part wasn't writing the SQL — it was agreeing on what the entities actually were before any code got written.”