如何创建相对于作为外键的主键自动生成的列

Question

In SQL Server Management Studio, I am creating this table:

CREATE TABLE Purchase 
(
     PurchaseID INT NOT NULL 
         FOREIGN KEY REFERENCES Product(ProductID) PRIMARY KEY,
     TotalQuantity INT NOT NULL,
     Price AS (PurchaseID.PRICE), 
     TotalPrice AS (TotalQuantity*Price),
     SalesAssistantID INT NOT NULL 
         FOREIGN KEY REFERENCES SalesAssistant(SalesAssistantID), 
     CashierID INT NOT NULL 
         FOREIGN KEY REFERENCES Cashier(CashierID)
)

Above code only represents what I want to achieve ( Price AS (PurchaseID.PRICE) ), Price should be created whenever the PurchaseID is specified so that TotalCost can also function automatically, I could not solve this problem. How to do it?

Answer 1

PurchaseID int identity(1,1) Primary key

这将purchaseID作为主键，而(1,1)表示它将从1开始并以1递增。