SQL-21-Days-Challenge by Indian Data Club

📅 Challenge Breakdown

• Duration: 21 days
• Focus: SQL fundamentals to advanced (queries, joins, subqueries, window functions, CTEs, optimization, modeling, and analytics)
• Structure: Daily topics paired with practical datasets & problem statements with resources.
• Goal: Equip you with strong SQL skills to query, clean, model, and analysis data — essential for roles in Data Analysis, Data Engineering, Data Science & AI and Software Development 🚀

🧾 Dataset Details

The primary dataset for this challenge is the Hospital Beds Management dataset.
Source: Kaggle – Hospital Beds Management

🍕 Mini Project: Pizza Analytics Challenge

Tables

1. orders: order_id, date, time
2. order_details: order_id, pizza_id, quantity
3. pizzas: pizza_id, pizza_type_id
4. pizza_types: pizza_type_id, name, category, ingredients.

Questions

Phase 1: Foundation & Inspection

1. Install IDC_Pizza.dump as IDC_Pizza server
2. List all unique pizza categories.
3. Display pizza_type_id, name, and ingredients, replacing NULL ingredients with "Missing Data". Show first 5 rows.
4. Check for pizzas missing a price.

Phase 2: Filtering & Exploration

1. Orders placed on '2015-01-01'.
2. List pizzas with price descending.
3. Pizzas sold in sizes 'L' or 'XL'.
4. Pizzas priced between $15.00 and $17.00.
5. Pizzas with "Chicken" in the name.
6. Orders on '2015-02-15' or placed after 8 PM.

Phase 3: Sales Performance

1. Total quantity of pizzas sold.
2. Average pizza price.
3. Total order value per order.
4. Total quantity sold per pizza category.
5. Categories with more than 5,000 pizzas sold.
6. Pizzas never ordered.
7. Price differences between different sizes of the same pizza.