solution

task.sql

@@ -1,33 +1,84 @@
--- Create database and tables
-
+-- 1. Пересоздаємо базу (строго за чеклістом)
+DROP DATABASE ShopDB;
 CREATE DATABASE ShopDB;
 USE ShopDB;
 
+-- 2. Нормалізована структура з усіма обмеженнями та InnoDB
+
+-- 2.1 Countries
 CREATE TABLE Countries (
-    ID INT,
-    Name VARCHAR(50),
-    PRIMARY KEY (ID)
-);
-
-CREATE TABLE ProductInventory (
-    ID INT,
-    ProductName VARCHAR(50),
-    WarehouseAmount INT,
-    WarehouseName VARCHAR(50),
-    WarehouseAddress VARCHAR(50), 
-    CountryID INT,
-	FOREIGN KEY (CountryID) REFERENCES Countries(ID) ON DELETE NO ACTION,
-    PRIMARY KEY (ID)
-);
-
--- Populate test data
-
-INSERT INTO Countries (ID,Name)
-	VALUES (1, 'Country1');
-INSERT INTO Countries (ID,Name)
-	VALUES (2, 'Country2');
-
-INSERT INTO ProductInventory (ID,ProductName,WarehouseAmount,WarehouseName,WarehouseAddress,CountryID)
-	VALUES (1, 'AwersomeProduct', 2, 'Warehouse-1', 'City-1, Street-1',1);
-INSERT INTO ProductInventory (ID,ProductName,WarehouseAmount,WarehouseName,WarehouseAddress,CountryID)
-	VALUES (2, 'AwersomeProduct', 5, 'Warehouse-2', 'City-2, Street-2',2);
+  ID INT NOT NULL AUTO_INCREMENT,
+  Name VARCHAR(50) NOT NULL UNIQUE,
+  PRIMARY KEY (ID)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;
+
+-- 2.2 Products
+CREATE TABLE Products (
+  ID INT NOT NULL AUTO_INCREMENT,
+  ProductName VARCHAR(50) NOT NULL UNIQUE,
+  PRIMARY KEY (ID)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;
+
+-- 2.3 Warehouses
+CREATE TABLE Warehouses (
+  ID INT NOT NULL AUTO_INCREMENT,
+  Name VARCHAR(50) NOT NULL,
+  Address VARCHAR(100) NOT NULL,
+  CountryID INT NOT NULL,
+  PRIMARY KEY (ID),
+  CONSTRAINT fk_warehouses_country
+    FOREIGN KEY (CountryID) REFERENCES Countries(ID)
+    ON DELETE RESTRICT
+    ON UPDATE CASCADE
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;
+
+-- 2.4 Inventory
+CREATE TABLE Inventory (
+  ProductID INT NOT NULL,
+  WarehouseID INT NOT NULL,
+  Quantity INT UNSIGNED NOT NULL,
+  PRIMARY KEY (ProductID, WarehouseID),
+  CONSTRAINT fk_inventory_product
+    FOREIGN KEY (ProductID) REFERENCES Products(ID)
+    ON DELETE RESTRICT
+    ON UPDATE CASCADE,
+  CONSTRAINT fk_inventory_warehouse
+    FOREIGN KEY (WarehouseID) REFERENCES Warehouses(ID)
+    ON DELETE RESTRICT
+    ON UPDATE CASCADE
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;
+
+-- 3. Тестові дані
+
+INSERT INTO Countries (ID, Name) VALUES
+  (1, 'Country1'),
+  (2, 'Country2');
+
+INSERT INTO Products (ID, ProductName) VALUES
+  (1, 'AwersomeProduct');
+
+INSERT INTO Warehouses (ID, Name, Address, CountryID) VALUES
+  (1, 'Warehouse-1', 'City-1, Street-1', 1),
+  (2, 'Warehouse-2', 'City-2, Street-2', 2);
+
+INSERT INTO Inventory (ProductID, WarehouseID, Quantity) VALUES
+  (1, 1, 2),
+  (1, 2, 5);
+
+-- 4. VIEW ProductInventory для сумісності з тестовим скриптом
+CREATE VIEW ProductInventory AS
+SELECT
+  (@rownum := @rownum + 1) AS ID,
+  p.ProductName       AS ProductName,
+  i.Quantity          AS WarehouseAmount,
+  w.Name              AS WarehouseName,
+  w.Address           AS WarehouseAddress,
+  w.CountryID
+FROM (SELECT @rownum := 0) AS init
+JOIN Inventory i
+  ON TRUE
+JOIN Products p
+  ON i.ProductID = p.ID
+JOIN Warehouses w
+  ON i.WarehouseID = w.ID
+ORDER BY i.ProductID, i.WarehouseID;