BEGIN TRANSACTION;

DECLARE @MaxCustomers int = 1000000;
DECLARE @CurrCustomer int = 1;
DECLARE @CustomerId int;
DECLARE @OrderId int;

--Initialize the items.
PRINT 'Initializing items'

INSERT INTO Item(itemName)
	VALUES('Item 1');

INSERT INTO Item(itemName)
	VALUES('Item 2');

INSERT INTO Item(itemName)
	VALUES('Item 3');

--Initialize the item details.
PRINT 'Initializing item details'
INSERT INTO ItemDetail(itemId, itemDetailPrice)
	(SELECT itemId, CONVERT(DECIMAL(5,2), itemId)
	FROM Item);

--Initialize the SKUs.
PRINT 'Initializing SKUs'
INSERT INTO Sku(sku)
	VALUES('SKU1');

INSERT INTO Sku(sku)
	VALUES('SKU2');

INSERT INTO Sku(sku)
	VALUES('SKU3');

--Initialize the Vendors.
PRINT 'Initializing vendors'
INSERT INTO Vendor(vendorName)
	VALUES('Vendor 1');

--Set the item - sku links.
PRINT 'Initializing item sku links'
INSERT INTO ItemSku(itemId, skuId)
	(SELECT itemId, skuId
	FROM Item, Sku
	WHERE itemName = 'Item 1'
	AND sku = 'SKU1');

INSERT INTO ItemSku(itemId, skuId)
	(SELECT itemId, skuId
	FROM Item, Sku
	WHERE itemName = 'Item 2'
	AND sku = 'SKU2');

INSERT INTO ItemSku(itemId, skuId)
	(SELECT itemId, skuId
	FROM Item, Sku
	WHERE itemName = 'Item 3'
	AND sku = 'SKU3');

--Set the vendor - sku links.
PRINT 'Initializing vendor sku links'
INSERT INTO VendorSku(vendorId, skuId)
	(SELECT vendorId, skuId
	FROM Vendor, Sku);

WHILE @CurrCustomer <= @MaxCustomers
BEGIN
	--PRINT 'Insert customer'
	INSERT INTO Customer(customerName, customerNumber)
		VALUES(CONCAT('Customer #', @CurrCustomer), RIGHT('0000000000' + @CurrCustomer, 10));

	SET @CustomerId = @@IDENTITY;

	--PRINT 'Insert order'
	INSERT INTO "Order"(customerId, orderNumber)
		VALUES(@CustomerId, CONCAT('Order #', @CurrCustomer));

	SET @OrderId = @@IDENTITY;

	--PRINT 'Insert order items'
	INSERT INTO OrderItem(orderId, itemDetailId, orderItemValue)
		(SELECT @OrderId, itemDetailId, CONCAT('some value ', itemDetailPrice)
		FROM ItemDetail);

	SET @CurrCustomer = @CurrCustomer + 1;

END;

--select * from customer;
--select * from "order";
--select * from orderitem;

COMMIT TRANSACTION;