Pizza Hut SQL Analysis Project

📌 Project Overview

This project provides an in-depth SQL analysis of a Pizza Hut database to extract valuable insights, such as order statistics, revenue generation, pizza popularity, and sales distribution. It consists of various SQL queries categorized into Basic, Intermediate, and Advanced levels to explore different aspects of the pizza sales data.

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📂 Database Schema

1. orders Table

Stores details of orders placed.

CREATE TABLE orders (
    order_id INT PRIMARY KEY,
    order_date DATE NOT NULL,
    order_time TIME NOT NULL
);

2. order_details Table

Stores details of individual pizzas ordered.

CREATE TABLE order_details (
    order_details_id INT PRIMARY KEY,
    order_id INT NOT NULL,
    pizza_id TEXT NOT NULL,
    quantity INT NOT NULL
);

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🛠 SQL Queries

🔹 Basic Queries

1. Retrieve the total number of orders placed

SELECT COUNT(order_id) AS total_orders FROM orders;

2. Calculate the total revenue generated from pizza sales

SELECT ROUND(SUM(order_details.quantity * pizzas.price), 0) AS total_revenue
FROM order_details 
JOIN pizzas ON order_details.pizza_id = pizzas.pizza_id;

3. Identify the highest-priced pizza

SELECT pizza_types.name, MAX(pizzas.price) AS highest_priced_pizza
FROM pizza_types 
JOIN pizzas ON pizza_types.pizza_type_id = pizzas.pizza_type_id
GROUP BY pizza_types.name 
ORDER BY highest_priced_pizza DESC 
LIMIT 1;

4. Identify the most common pizza size ordered

SELECT pizzas.size, COUNT(order_details.order_details_id) AS most_common_pizza_size_ordered
FROM pizzas 
JOIN order_details ON pizzas.pizza_id = order_details.pizza_id
GROUP BY pizzas.size
ORDER BY most_common_pizza_size_ordered DESC 
LIMIT 1;

5. List the top 5 most ordered pizza types along with their quantities

SELECT pizza_types.name, SUM(order_details.quantity) AS most_ordered_pizza
FROM pizza_types 
JOIN pizzas ON pizza_types.pizza_type_id = pizzas.pizza_type_id
JOIN order_details ON order_details.pizza_id = pizzas.pizza_id
GROUP BY pizza_types.name
ORDER BY most_ordered_pizza DESC 
LIMIT 5;

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🔹 Intermediate Queries

1. Find the total quantity of each pizza category ordered

SELECT pizza_types.category, SUM(order_details.quantity) AS total_quantity
FROM pizza_types 
JOIN pizzas ON pizza_types.pizza_type_id = pizzas.pizza_type_id
JOIN order_details ON order_details.pizza_id = pizzas.pizza_id
GROUP BY pizza_types.category;

2. Determine the distribution of orders by hour of the day

SELECT HOUR(orders.order_time) AS order_hour, COUNT(order_id) AS total_orders
FROM orders 
GROUP BY HOUR(orders.order_time);

3. Find the category-wise distribution of pizzas

SELECT category, COUNT(name) AS pizza_count
FROM pizza_types
GROUP BY category;

4. Calculate the average number of pizzas ordered per day

SELECT ROUND(AVG(quantity), 0) AS avg_pizzas_per_day
FROM (
    SELECT orders.order_date, SUM(order_details.quantity) AS quantity
    FROM orders 
    JOIN order_details ON orders.order_id = order_details.order_id
    GROUP BY orders.order_date
) AS order_quantity;

5. Determine the top 3 most ordered pizza types based on revenue

SELECT pizza_types.name, ROUND(SUM(order_details.quantity * pizzas.price), 0) AS total_revenue
FROM pizza_types 
JOIN pizzas ON pizza_types.pizza_type_id = pizzas.pizza_type_id
JOIN order_details ON order_details.pizza_id = pizzas.pizza_id
GROUP BY pizza_types.name
ORDER BY total_revenue DESC 
LIMIT 3;

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🔹 Advanced Queries

1. Calculate the percentage contribution of each pizza type to total revenue

SELECT pizza_types.name,
    ROUND(SUM(order_details.quantity * pizzas.price) / 
    (SELECT ROUND(SUM(order_details.quantity * pizzas.price), 2)
     FROM order_details 
     JOIN pizzas ON order_details.pizza_id = pizzas.pizza_id) * 100, 2) AS revenue_percentage
FROM pizza_types 
JOIN pizzas ON pizza_types.pizza_type_id = pizzas.pizza_type_id
JOIN order_details ON order_details.pizza_id = pizzas.pizza_id
GROUP BY pizza_types.name;

2. Analyze the cumulative revenue generated over time

SELECT order_date,
       SUM(total_revenue) OVER (ORDER BY order_date) AS cumulative_revenue
FROM (
    SELECT orders.order_date, ROUND(SUM(order_details.quantity * pizzas.price), 0) AS total_revenue
    FROM order_details 
    JOIN pizzas ON order_details.pizza_id = pizzas.pizza_id
    JOIN orders ON orders.order_id = order_details.order_id
    GROUP BY orders.order_date
) AS total_sales;

3. Determine the top 3 most ordered pizza types based on revenue for each pizza category

WITH ranked_pizza_types AS (
    SELECT pizza_types.name, pizza_types.category,
           SUM(order_details.quantity * pizzas.price) AS total_revenue,
           RANK() OVER (PARTITION BY pizza_types.category ORDER BY SUM(order_details.quantity * pizzas.price) DESC) AS rnk
    FROM order_details 
    JOIN pizzas ON order_details.pizza_id = pizzas.pizza_id
    JOIN pizza_types ON pizza_types.pizza_type_id = pizzas.pizza_type_id
    GROUP BY pizza_types.name, pizza_types.category
)
SELECT name, category, total_revenue, rnk
FROM ranked_pizza_types
WHERE rnk <= 3;

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📌 Conclusion

This project utilizes SQL queries to analyze pizza sales data effectively. By leveraging JOINs, GROUP BY, aggregate functions, window functions, and ranking, we uncover valuable insights that can help optimize sales and inventory management.

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📜 Author

Project by: Ayonika Dutta