Solution

task.sql

@@ -1,33 +1,62 @@
 -- Create database and tables
-
+DROP DATABASE IF EXISTS ShopDB;
 CREATE DATABASE ShopDB;
 USE ShopDB;
 
+-- Countries table
 CREATE TABLE Countries (
-    ID INT,
+    ID   INT,
     Name VARCHAR(50),
     PRIMARY KEY (ID)
 );
 
+-- Products table
+CREATE TABLE Products (
+    ID   INT,
+    Name VARCHAR(50),
+    PRIMARY KEY (ID)
+);
+
+-- Warehouses table
+CREATE TABLE Warehouses (
+    ID        INT,
+    Name      VARCHAR(50),
+    Address   VARCHAR(50),
+    CountryID INT,
+    FOREIGN KEY (CountryID) REFERENCES Countries(ID) ON DELETE NO ACTION,
+    PRIMARY KEY (ID)
+);
+
+-- ProductInventory table
 CREATE TABLE ProductInventory (
-    ID INT,
-    ProductName VARCHAR(50),
+    ID              INT,
+    ProductID       INT,
     WarehouseAmount INT,
-    WarehouseName VARCHAR(50),
-    WarehouseAddress VARCHAR(50), 
-    CountryID INT,
-	FOREIGN KEY (CountryID) REFERENCES Countries(ID) ON DELETE NO ACTION,
+    WarehouseID     INT,
+    FOREIGN KEY (ProductID)   REFERENCES Products(ID)    ON DELETE NO ACTION,
+    FOREIGN KEY (WarehouseID) REFERENCES Warehouses(ID) ON DELETE NO ACTION,
     PRIMARY KEY (ID)
 );
 
+-- =========================
 -- Populate test data
+-- =========================
+
+-- Countries
+INSERT INTO Countries (ID, Name)
+VALUES (1, 'Country1'),
+       (2, 'Country2');
+
+-- Products
+INSERT INTO Products (ID, Name)
+VALUES (1, 'AwesomeProduct');
+
+-- Warehouses
+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 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);
+-- Product inventory
+INSERT INTO ProductInventory (ID, ProductID, WarehouseAmount, WarehouseID)
+VALUES (1, 1, 2, 1),
+       (2, 1, 5, 2);