1

create-database.sql

@@ -1,44 +1,35 @@
+DROP DATABASE IF EXISTS ShopDB;
 CREATE DATABASE ShopDB;
 USE ShopDB;
 
 CREATE TABLE Products (
-    ID INT AUTO_INCREMENT,
+    ID INT AUTO_INCREMENT PRIMARY KEY,
     Name VARCHAR(50),
     Description VARCHAR(100),
     Price INT,
-    WarehouseAmount INT,
-    PRIMARY KEY (ID)
+    WarehouseAmount INT
 );
 
 CREATE TABLE Customers (
-    ID INT AUTO_INCREMENT,
+    ID INT AUTO_INCREMENT PRIMARY KEY,
     FirstName VARCHAR(50),
     LastName VARCHAR(50),
-    Email VARCHAR(50),
-    Address VARCHAR(50),
-    PRIMARY KEY (ID)
+    Email VARCHAR(100),
+    Address VARCHAR(50)
 );
 
 CREATE TABLE Orders (
-    ID INT AUTO_INCREMENT,
-    CustomerID INT, 
-    FOREIGN KEY (CustomerID) REFERENCES Customers(ID) ON DELETE SET NULL,
+    ID INT AUTO_INCREMENT PRIMARY KEY,
+    CustomerID INT,
     Date DATE,
-    PRIMARY KEY (ID)
+    FOREIGN KEY (CustomerID) REFERENCES Customers(ID) ON DELETE SET NULL
 );
 
 CREATE TABLE OrderItems (
-    ID INT AUTO_INCREMENT,
-    OrderID INT, 
-    FOREIGN KEY (OrderID) REFERENCES Orders(ID) ON DELETE SET NULL,
-	ProductID INT, 
+    ID INT AUTO_INCREMENT PRIMARY KEY,
+    OrderID INT,
+    ProductID INT,
     Count INT,
-    FOREIGN KEY (ProductID) REFERENCES Products(ID) ON DELETE SET NULL,
-    PRIMARY KEY (ID)
+    FOREIGN KEY (OrderID) REFERENCES Orders(ID) ON DELETE SET NULL,
+    FOREIGN KEY (ProductID) REFERENCES Products(ID) ON DELETE SET NULL
 );
-
-INSERT INTO Products (Name, Description, Price, WarehouseAmount)
-	VALUES ('AwersomeProduct', 'Product Desctiption', 5, 42);
-
-INSERT INTO Customers (FirstName, LastName, Email, Address)
-	VALUES ('John', 'Dou', 'j@dou.ua', 'far, far away');

task.sql

@@ -2,10 +2,22 @@
 USE ShopDB; 
 
 -- Some data should be created outside the transaction (here)
+INSERT INTO Products (ID, Name, Description, Price, WarehouseAmount)
+VALUES (1, 'AwersomeProduct', 'A great product', 100, 42);
 
+INSERT INTO Customers (ID, FirstName, LastName, Email, Address)
+VALUES (1, 'John', 'Doe', 'john.doe@example.com', '123 Main St');
+
+INSERT INTO Orders (CustomerID, Date)     
+VALUES (1, '2023-01-01');
 -- Start the transaction 
-START TRANSACTION; 
+START TRANSACTION;
+
+INSERT INTO OrderItems (OrderID, ProductID, Count)
+VALUES (LAST_INSERT_ID(), 1, 1);
 
--- And some data should be created inside the transaction 
+UPDATE Products
+SET WarehouseAmount = WarehouseAmount - 1
+WHERE ID = 1;
 
-COMMIT; 
+COMMIT;