如何在存储过程中检查该值是否为null？

Question

SQL Server Management Studio,存储过程

我customerName从Visual Studio 传递,并在存储过程中我想得到customerID.

现在我想检查是否customerId为null,这意味着这是一个新客户.如果是这样,我想在表中插入该客户.然后我想获得客户ID,并希望存储TableB.

这是示例代码:

还告诉如何执行

if(@customerId == null)
{
   Insert customerDetails into CustomerTable;
   get CustomerId.
} //General workflow what i want.

为此,我编写了一个SQL Server存储过程

create procedure Customers_AddData2    
    @CustomerName nvarchar(50) = null
As     
   --Get Customer ID
   declare @CustomerID numeric(18, 0)= (SELECT distinct [CustomerID] FROM [tblCustomerMaster] WHERE CustomerName = @CustomerName)

  --checking if customerId not found
  -- Here is some error, Not getting syntax 

  IF(@CustomerID IS NULL == true)  
  {
      INSERT INTO [tblCustomerMaster] ([CustomerName]) 
      VALUES (CustomerName)
  }

  -- Now get customer id
  @CustomerID numeric(18, 0)= (SELECT distinct [CustomerID] FROM [tblCustomerMaster] WHERE CustomerName = @CustomerName)

Answer 1

刚刚IF(@CustomerID IS NULL)够

IF(@CustomerID IS NULL)
BEGIN
     --insert here..
      INSERT INTO [tblCustomerMaster]
     ([CustomerName]

    VALUES

    (CustomerName)
    SET @CustomerID = Scope_Identity() -- sql server syntax to get the ID after insert..
END 
ELSE
BEGIN
   -- update perhaps..
END