Simple MySQL example for E-commice

Source: Dev.to

Hi everyone, I wanted to share my experience with SQL. Below is a simple e‑commerce schema illustrating the main tables and relationships.

Role Table

-- Role table
CREATE TABLE role (
    id INT AUTO_INCREMENT PRIMARY KEY,
    name VARCHAR(50) NOT NULL UNIQUE,
    description VARCHAR(255)
);

-- Insert default roles
INSERT INTO role (name, description) VALUES
    ('admin', 'Full system access'),
    ('customer', 'Can browse and place orders'),
    ('staff', 'Can manage orders and products'),
    ('vendor', 'Supplier with limited access');

User Table

CREATE TABLE user (
    id INT AUTO_INCREMENT PRIMARY KEY,
    role_id INT NOT NULL,
    first_name VARCHAR(100) NOT NULL,
    last_name VARCHAR(100) NOT NULL,
    email VARCHAR(255) NOT NULL UNIQUE,
    password_hash VARCHAR(255) NOT NULL,
    phone VARCHAR(20),
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    FOREIGN KEY (role_id) REFERENCES role(id)
);

Producer Table (linked to a user)

CREATE TABLE producer (
    id INT AUTO_INCREMENT PRIMARY KEY,
    user_id INT NOT NULL UNIQUE,
    bio TEXT,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    FOREIGN KEY (user_id) REFERENCES user(id) ON DELETE CASCADE
);

Category Table

CREATE TABLE category (
    id INT AUTO_INCREMENT PRIMARY KEY,
    name VARCHAR(100) NOT NULL UNIQUE
);

-- Insert default categories
INSERT INTO category (name) VALUES
    ('Vegetables'),
    ('Fruits'),
    ('Dairy'),
    ('Honey & Preserves'),
    ('Meat & Poultry'),
    ('Drinks'),
    ('Bakery'),
    ('Herbs & Flowers');

Product Table

CREATE TABLE product (
    id INT AUTO_INCREMENT PRIMARY KEY,
    producer_id INT NOT NULL,
    category_id INT NOT NULL,
    name VARCHAR(255) NOT NULL,
    description TEXT,
    price DECIMAL(10, 2) NOT NULL,
    stock_qty INT NOT NULL DEFAULT 0,
    unit VARCHAR(50) NOT NULL DEFAULT 'item',
    is_organic BOOLEAN DEFAULT FALSE,
    is_available BOOLEAN DEFAULT TRUE,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    FOREIGN KEY (producer_id) REFERENCES producer(id) ON DELETE CASCADE,
    FOREIGN KEY (category_id) REFERENCES category(id)
);

Address Table

CREATE TABLE address (
    id INT AUTO_INCREMENT PRIMARY KEY,
    user_id INT NOT NULL,
    street VARCHAR(255) NOT NULL,
    city VARCHAR(100) NOT NULL,
    postcode VARCHAR(20) NOT NULL,
    country VARCHAR(100) NOT NULL DEFAULT 'United Kingdom',
    is_default BOOLEAN DEFAULT FALSE,
    FOREIGN KEY (user_id) REFERENCES user(id) ON DELETE CASCADE
);

Order Table

CREATE TABLE `order` (
    id INT AUTO_INCREMENT PRIMARY KEY,
    user_id INT NOT NULL,
    address_id INT NOT NULL,
    status ENUM('pending', 'confirmed', 'processing', 'shipped', 'delivered', 'cancelled') DEFAULT 'pending',
    total_price DECIMAL(10, 2) NOT NULL,
    payment_status ENUM('unpaid', 'paid', 'refunded') DEFAULT 'unpaid',
    payment_method VARCHAR(50),
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    FOREIGN KEY (user_id) REFERENCES user(id),
    FOREIGN KEY (address_id) REFERENCES address(id)
);

Order Item Table

CREATE TABLE order_item (
    id INT AUTO_INCREMENT PRIMARY KEY,
    order_id INT NOT NULL,
    product_id INT NOT NULL,
    quantity INT NOT NULL DEFAULT 1,
    unit_price DECIMAL(10, 2) NOT NULL,
    FOREIGN KEY (order_id) REFERENCES `order`(id) ON DELETE CASCADE,
    FOREIGN KEY (product_id) REFERENCES product(id)
);

Any feedback or suggestions for improvement would be appreciated!