WS10

2026-06-22 23:39:36 +03:30
parent 00f990c653
commit 5ea8a95fe7
22 changed files with 779 additions and 253 deletions
@@ -1,141 +1,37 @@
-- 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.
+CREATE TABLE users (
+                       id SERIAL PRIMARY KEY,
+                       username VARCHAR(50) UNIQUE NOT NULL,
+                       password_hash VARCHAR(255) NOT NULL,
+                       email VARCHAR(100)
+);

+CREATE TABLE menu_items (
+                            id SERIAL PRIMARY KEY,
+                            name VARCHAR(100) NOT NULL,
+                            description TEXT,
+                            price NUMERIC(10, 2) NOT NULL CHECK (price > 0),
+                            category VARCHAR(50)
+);

+CREATE TABLE orders (
+                        id SERIAL PRIMARY KEY,
+                        user_id INT NOT NULL,
+                        created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+                        total_price NUMERIC(10, 2) NOT NULL,
+                        CONSTRAINT fk_user FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE
+);

-- =======================================================
-- 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 order_details (
+                               id SERIAL PRIMARY KEY,
+                               order_id INT NOT NULL,
+                               menu_item_id INT NOT NULL,
+                               quantity INT NOT NULL CHECK (quantity > 0),
+                               unit_price NUMERIC(10, 2) NOT NULL,
+                               CONSTRAINT fk_order FOREIGN KEY (order_id) REFERENCES orders(id) ON DELETE CASCADE,
+                               CONSTRAINT fk_menu_item FOREIGN KEY (menu_item_id) REFERENCES menu_items(id)
+);

-
-
-- =======================================================
-- 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 ...
-
-
-
-- =======================================================
-- 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 ...
-
-
-
-- =======================================================
-- 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 ...
-
-
-
-- =======================================================
-- 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 ...
-
-
-
-- =======================================================
-- VERIFICATION QUERIES
-- =======================================================
--
-- Uncomment these queries to verify your database.
--
-- SELECT * FROM ...;
-- SELECT * FROM ...;
-- SELECT * FROM ...;
-- SELECT * FROM ...;
+INSERT INTO menu_items (name, description, price, category) VALUES
+                                                                ('Margherita Pizza', 'Classic cheese and tomato', 10.00, 'Pizza'),
+                                                                ('Cheeseburger', 'Beef patty with cheese', 8.00, 'Burger'),
+                                                                ('Spaghetti Carbonara', 'Pasta with creamy sauce and bacon', 12.00, 'Pasta');