Files
IPZ_1/docs/01-overview.md
2026-05-17 21:27:42 +02:00

99 lines
4.9 KiB
Markdown
Raw Blame History

This file contains ambiguous Unicode characters
This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.
# Hotel Reservations — Data Warehouse Project
## Project Summary
This project implements a complete **Data Warehousing pipeline** for a hotel reservation system, covering all standard DW layers:
```
MySQL OLTP ──► Apache NiFi ETL ──► Oracle Data Mart ──► Power BI Reports
(source) (transform) (analytical store) (OLAP queries)
```
The system is built around the **A.24 Hotel Reservations** domain from the course specification. The OLTP database was populated with **~635,000 synthetically generated rows** covering 200 hotels, 100,000 guests, 500,000 bookings, and 531,000 room bookings across a 4-year period (20222025).
---
## Business Context
A hotel chain needs to answer questions like:
- Which countries generate the most revenue per quarter?
- How does occupancy differ between peak and off-peak seasons?
- What is the revenue contribution of 5-star vs 3-star hotels?
- How has a hotel's revenue changed after upgrading its star rating?
These questions require **historical, multi-dimensional analysis** that a normalized OLTP database cannot serve efficiently. The data mart provides pre-modelled, denormalized data optimized for analytical queries.
---
## Architecture
```
┌─────────────────────────────────────────────────────────┐
│ SOURCE LAYER │
│ MySQL 8.4 (Docker/Podman, port 13306) │
│ Database: hotel_reservations │
│ 13 normalized tables, ~635K rows │
└───────────────────────┬─────────────────────────────────┘
│ JDBC (MySqlConnector)
┌─────────────────────────────────────────────────────────┐
│ ETL LAYER │
│ Apache NiFi │
│ 5 Process Groups: Date Dim / Static Dims / │
│ SCD2 Hotel / SCD1 Guest / Incremental Fact │
└───────────────────────┬─────────────────────────────────┘
│ JDBC (Oracle JDBC)
┌─────────────────────────────────────────────────────────┐
│ DATA MART LAYER │
│ Oracle (university lab schema) │
│ Star schema: 6 dimensions + 1 fact table │
│ SCD Type 2 on DIM_HOTEL │
└───────────────────────┬─────────────────────────────────┘
┌─────────────────────────────────────────────────────────┐
│ PRESENTATION LAYER │
│ Power BI Desktop │
│ OLAP reports via DirectQuery / Import │
└─────────────────────────────────────────────────────────┘
```
---
## Technology Stack
| Component | Technology | Version |
|-----------|-----------|---------|
| OLTP Database | MySQL | 8.4 |
| Container runtime | Docker / Podman | — |
| Data generator | C# (.NET) | 10 |
| ETL tool | Apache NiFi | — |
| Data Mart | Oracle RDBMS | university lab |
| Reporting | Power BI Desktop | — |
---
## Repository Structure
```
IPZ_1/
├── docker/
│ ├── start.sh # Start MySQL container (Linux/macOS)
│ ├── stop.sh # Stop MySQL container
│ ├── start.ps1 # Start MySQL container (Windows)
│ └── stop.ps1 # Stop MySQL container
├── sql/
│ ├── schema.sql # MySQL OLTP DDL
│ └── datamart_schema.sql # Oracle Data Mart DDL
├── generator/
│ └── generate.cs # .NET 10 data generator script
└── docs/
├── 01-overview.md # This file
├── 02-oltp.md # OLTP database design
├── 03-datamart.md # Data mart design
├── 04-setup.md # Setup and run guide
└── nifi-flow.md # NiFi ETL flow reference
```