用于插入的SQL Server存储过程运行，但不会将值插入到表中

Question

我已经编写了此存储过程以将行项添加到名为InvoiceLineItems的表中。数据库确实有一些测试条目，并且此过程基于正在工作的其他插入存储过程。

由于某种原因，查询将会成功执行，但这些值实际上并未插入到表中，而且我无法弄清楚为什么，尤其是因为其他插入过程已经奏效。

代码，它成功地将值插入表：

IF OBJECT_ID('sp_InsertInvoiceLineitems') IS NOT NULL 
    DROP PROC sp_InsertInvoiceLineitems; 
GO 

CREATE PROC sp_InsertInvoiceLineitems 
    @InvoiceID INT = NULL, 
    @ProductID INT = NULL, 
    @PQty TINYINT = NULL, 
    @ListPrice MONEY = NULL, 
    @ServiceID INT = NULL, 
    @ServiceCost MONEY = NULL, 
    @SQty TINYINT = NULL, 
    @TotalAmount MONEY = NULL 
AS 
BEGIN 
    IF @InvoiceID IS NULL 
     THROW 50001, 'Must enter an InvoiceID.', 1; 

    IF @ProductID IS NOT NULL AND @ProductID NOT IN (SELECT ProductID FROM Products) 
     THROW 50001, 'Please enter a valid ProductID.', 1; 

    IF @PQty IS NOT NULL AND @ProductID IS NOT NULL AND @PQty <= 0 
     THROW 50001, 'PQty must be greater than zero.', 1; 

    IF @ProductID IS NOT NULL 
     SET @ListPrice = (SELECT ListPrice FROM Products WHERE ProductID = @ProductID); 

    IF @ServiceID IS NOT NULL AND @ServiceID NOT IN (SELECT ServiceID FROM Services) 
     THROW 50001, 'Please enter a valid ServiceID.', 1; 

    IF @ServiceID IS NOT NULL 
     SET @ServiceCost = (SELECT ServiceCost FROM Services WHERE ServiceID = @ServiceID); 

    IF @SQty IS NOT NULL AND @ServiceID IS NOT NULL AND @Sqty <= 0 
     THROW 50001, 'SQty must be greater than zero.', 1; 

    IF @ProductID IS NOT NULL OR @ServiceID IS NOT NULL 
     SET @TotalAmount = ((@ListPrice*@PQty) + (@ServiceCost*@SQty)); 
    ELSE --All data is verified 
     INSERT INTO InvoiceLineItems (InvoiceID, ProductID, PQty, ListPrice, ServiceID, ServiceCost, SQty, TotalAmount) 
     VALUES (@InvoiceID, @ProductID, @PQty, @ListPrice, @ServiceID, @ServiceCost, @SQty, @TotalAmount); 
END 
GO 

为什么它不插入值的任何想法：

IF OBJECT_ID('sp_InsertInvoices') IS NOT NULL 
    DROP PROC sp_InsertInvoices; 
GO 

CREATE PROC sp_InsertInvoices 
    @CustomerID INT = NULL, 
    @TotalDue MONEY = NULL, 
    @Paid CHAR(3) = NULL 
AS 
BEGIN 
    IF @CustomerID IS NULL 
     THROW 50001, 'CustomerID cannot be null.', 1; 

    IF @TotalDue IS NULL 
     THROW 50001, 'TotalDue cannot be Null.', 1; 

    IF @TotalDue < 0 
     THROW 50001, 'TotalDue cannot be negative.', 1; 

    IF @Paid IS NULL 
     THROW 50001, 'Must specify if the balance is paid or not.', 1; 
    ELSE --All data is validated 
     INSERT INTO Invoices (CustomerID, TotalDue, Paid) 
     VALUES (@CustomerID, @TotalDue, @Paid) 
END 
GO 

不插入值的代码？

Answer 1

在IF...ELSE中，ELSE或补充IF仅在前面的IF语句不满足时才执行。因此：

IF @ProductID IS NOT NULL SET @ListPrice = (SELECT ListPrice FROM Products WHERE ProductID = @ProductID)

如果返回TRUE你的声明会终止，你会设置了@ListPrice。

您需要检查所有的错误就像你在你的第一个声明中所做的，如果所有条件都得不到满足（没有错误），然后设置你的变量和更新（插入）到表中。