📑 Table of Contents

1. Why Table Module Matters
2. What is Table Module?
3. Analogy: The School Office
4. Python Example: Orders Table
5. When to Use & When to Avoid
6. Curiosities & Recommendations
7. GitHub Repo + Automation
8. Final Thoughts

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🔥 Why Table Module Matters

In enterprise apps, business logic can live in different places:

• In the database (stored procedures).
• In domain models (one class per row).
• Or in a table module: one class per table.

👉 Table Module keeps all rules for a table in a single place, making code easier to read and maintain when logic is simple.

---

📖 What is Table Module?

Definition:

A single class that handles the business logic for all rows in a database table or view.

⚖️ Difference with Domain Model:

• Domain Model → 1 class per row.
• Table Module → 1 class per table.

---

🧩 Analogy: The School Office

Imagine a school secretary’s office:

• Instead of every teacher managing attendance (Domain Model),
• The office manages attendance records for the whole school (Table Module).

📌 Centralized, consistent, and simple.

---

💻 Python Example: Orders Table

❌ Without Table Module (spaghetti logic)

import sqlite3

conn = sqlite3.connect(":memory:")
cursor = conn.cursor()
cursor.execute("CREATE TABLE orders (id INTEGER, customer TEXT, total REAL)")
cursor.executemany("INSERT INTO orders VALUES (?, ?, ?)", [
(1, "Alice", 120.0),
(2, "Bob", 80.5),
(3, "Alice", 45.0)
])

# Logic spread everywhere 😓
cursor.execute("SELECT SUM(total) FROM orders WHERE customer='Alice'")
print("Alice total:", cursor.fetchone()[0])

❌ Problem: Logic is scattered in SQL queries all over the app.

---

✅ With Table Module

import sqlite3

class OrdersTable:
def __init__(self, connection):
self.conn = connection

def total_sales(self):
cursor = self.conn.cursor()
cursor.execute("SELECT SUM(total) FROM orders")
return cursor.fetchone()[0]

def sales_by_customer(self, customer):
cursor = self.conn.cursor()
cursor.execute("SELECT SUM(total) FROM orders WHERE customer=?", (customer,))
return cursor.fetchone()[0]

# Setup DB
conn = sqlite3.connect(":memory:")
cursor = conn.cursor()
cursor.execute("CREATE TABLE orders (id INTEGER, customer TEXT, total REAL)")
cursor.executemany("INSERT INTO orders VALUES (?, ?, ?)", [
(1, "Alice", 120.0),
(2, "Bob", 80.5),
(3, "Alice", 45.0)
])

# Usage
orders = OrdersTable(conn)
print("Total Sales:", orders.total_sales())
print("Alice Sales:", orders.sales_by_customer("Alice"))

✅ SRP: All business logic lives in OrdersTable.

✅ Reusability: Centralized methods.

✅ KISS: Simple & clean.

---

🤔 When to Use & When to Avoid

✅ Use Table Module when:

• Business rules are simple.
• You need reports or aggregations.
• Tables are the main unit of work.

❌ Avoid when:

• Each row has complex behavior.
• You need polymorphism → prefer Domain Model.

---

🧠 Curiosities & Recommendations

💡 Did you know?

• Table Module was a stepping stone before modern ORMs like SQLAlchemy or Django ORM.
• Many legacy apps still hide Table Modules inside stored procedures.
• Fowler recommends it for reporting systems.

👉 Pro tip: Use Table Module for data-centric apps, Domain Model for behavior-rich apps.

---

📦 GitHub Repo + Automation

Repo structure:

enterprise-table-module/
├─ table_module.py
├─ tests/
│   └─ test_table_module.py
├─ requirements.txt
└─ .github/
└─ workflows/
└─ ci.yml

requirements.txt

pytest==8.3.3

.github/workflows/ci.yml

name: Python CI

on: [push, pull_request]

jobs:
test:
runs-on: ubuntu-latest
steps:
- uses: actions/checkout@v3
- uses: actions/setup-python@v4
with:
python-version: '3.11'
- run: pip install -r requirements.txt
- run: pytest

🔗 GitHub Repository Example

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🎯 Final Thoughts

The Table Module pattern is a powerful yet underrated way to structure enterprise apps when logic is simple and table-oriented.

✨ Remember:

• Use it for reports and aggregations.
• Switch to Domain Model when rules grow complex.

✍️ Your turn! Would you use Table Module in your next project?

Let me know in the comments 👇