Implemented database schema

Implemented DAOs
Updated models
Implemented Services

database.sql

@@ -1,141 +1,76 @@
--- Restaurant Database Management System
---
--- Instructions:
--- 1. Create all required tables.
--- 2. Design appropriate PRIMARY KEY and FOREIGN KEY relationships.
--- 3. Add suitable constraints based on the requirements.
--- 4. Insert initial mock data.
--- 5. Insert at least 3 menu items.
--- 6. The script should be executable from start to finish without errors.
-
-
-
 -- =======================================================
 -- USER TABLE
 -- =======================================================
---
--- Represents customers using the system.
---
--- Required information:
--- - Unique identifier
--- - Username
--- - Password
--- - Email (optional)
---
--- Requirements:
--- - Each user must have a unique identifier.
--- - Usernames must be unique.
--- - Username and password are required.
--- - Passwords should not be stored in plain text.
---
--- CREATE TABLE ...
-
 
+CREATE TABLE users(
+    id SERIAL PRIMARY KEY,
+    username VARCHAR(50) UNIQUE NOT NULL,
+    password_hash TEXT NOT NULL,
+    email VARCHAR(250)
+);
 
 -- =======================================================
 -- MENU ITEM TABLE
 -- =======================================================
---
--- Represents available food and drink items.
---
--- Required information:
--- - Unique identifier
--- - Name
--- - Description (optional)
--- - Price
--- - Category (optional)
---
--- Requirements:
--- - Each menu item must have a unique identifier.
--- - Name is required.
--- - Price must always be positive.
---
--- CREATE TABLE ...
-
 
+CREATE TABLE menu(
+    id SERIAL PRIMARY KEY,
+    name VARCHAR(250) NOT NULL,
+    description TEXT,
+    price NUMERIC NOT NULL CHECK (price > 0),
+    category VARCHAR(50)
+);
 
 -- =======================================================
 -- ORDER TABLE
 -- =======================================================
---
--- Represents orders placed by customers.
---
--- Required information:
--- - Unique identifier
--- - Reference to customer
--- - Creation date and time
--- - Total price
---
--- Requirements:
--- - Each order must belong to exactly one user.
--- - A user can have multiple orders.
--- - The relationship between User and Order must be implemented.
---
--- Note:
--- Avoid using reserved SQL keywords as table names.
--- Consider using a name such as "orders" or "customer_orders".
---
--- CREATE TABLE ...
 
+CREATE TABLE orders (
+    id SERIAL PRIMARY KEY,
+    user_id INT NOT NULL,
+    created_at TIMESTAMP NOT NULL,
+    total_price NUMERIC NOT NULL,
 
+    FOREIGN KEY (user_id) REFERENCES users(id)
+);
 
 -- =======================================================
 -- ORDER DETAIL TABLE
 -- =======================================================
---
--- Represents items inside an order.
---
--- Required information:
--- - Unique identifier
--- - Reference to an order
--- - Reference to a menu item
--- - Quantity
--- - Item price at purchase time
---
--- Requirements:
--- - Each detail record must belong to one order.
--- - Each detail record must reference one menu item.
--- - Quantity must always be greater than zero.
--- - Store the item's price at the moment of purchase.
---
--- CREATE TABLE ...
 
+CREATE TABLE order_details(
+    id SERIAL PRIMARY KEY,
+    order_id INT NOT NULL,
+    menu_id INT NOT NULL,
+    quantity NUMERIC NOT NULL CHECK (quantity > 0),
+    item_price NUMERIC NOT NULL CHECK (item_price > 0),
 
+    FOREIGN KEY (order_id) REFERENCES orders(id),
+    FOREIGN KEY (menu_id) REFERENCES menu(id)
+);
 
 -- =======================================================
 -- INITIAL MENU DATA
 -- =======================================================
---
--- Insert at least 3 food or drink items.
---
--- Example categories:
--- - Pizza
--- - Burger
--- - Pasta
--- - Drink
---
--- INSERT INTO ...
-
-
-
--- =======================================================
--- OPTIONAL TEST DATA
--- =======================================================
---
--- You may insert sample users and orders for testing.
--- This section is optional.
---
--- INSERT INTO ...
-
 
+insert into menu (name, description, price, category) values ('Margherita Pizza', 'Classic pizza with tomato sauce, mozzarella, and basil.', 12.99, 'Pizza');
+insert into menu (name, description, price, category) values ('Pepperoni Pizza', null, 14.49, 'Pizza');
+insert into menu (name, description, price, category) values ('Cheeseburger', 'Beef patty with cheddar cheese, lettuce, and tomato.', 10.99, 'Burger');
+insert into menu (name, description, price, category) values ('Chicken Burger', null, 11.49, 'Burger');
+insert into menu (name, description, price, category) values ('Caesar Salad', 'Romaine lettuce, croutons, parmesan, and Caesar dressing.', 8.99, 'Salad');
+insert into menu (name, description, price, category) values ('Greek Salad', null, 9.49, 'Salad');
+insert into menu (name, description, price, category) values ('French Fries', 'Crispy golden potato fries.', 4.99, 'Side');
+insert into menu (name, description, price, category) values ('Onion Rings', null, 5.49, 'Side');
+insert into menu (name, description, price, category) values ('Espresso', null, 2.99, 'Drink');
+insert into menu (name, description, price, category) values ('Cappuccino', 'Espresso with steamed milk and milk foam.', 4.49, 'Drink');
+insert into menu (name, description, price, category) values ('Chocolate Cake', null, 6.99, 'Dessert');
+insert into menu (name, description, price, category) values ('Cheesecake', 'Creamy cheesecake served with berry sauce.', 7.49, 'Dessert');
 
 -- =======================================================
 -- VERIFICATION QUERIES
 -- =======================================================
---
--- Uncomment these queries to verify your database.
---
--- SELECT * FROM ...;
--- SELECT * FROM ...;
--- SELECT * FROM ...;
--- SELECT * FROM ...;
+
+SELECT * FROM users;
+SELECT * FROM menu;
+SELECT * FROM orders;
+SELECT * FROM order_details;