存储过程结果？

Question

我有一个存储过程调用其他存储过程，然后返回一条消息。然而，SP并不如预期运行：

ALTER PROCEDURE [dbo].[sp_Test] 
    -- Add the parameters for the stored procedure here 
    @ID int, 
    @UN nvarchar(30), 
    @PW nvarchar(30), 
    @Message nvarchar(50) out 
AS 
BEGIN 
    -- SET NOCOUNT ON added to prevent extra result sets from 
    -- interfering with SELECT statements. 
    SET NOCOUNT ON; 
    -- Variables 
    Declare @ValidUser nvarchar(75); 
    Declare @Current nvarchar(50); 
    Declare @Log bit = 0; 
    Declare @LogDateTime datetime2 = getdate(); 

    Execute @ValidUser = sp_UserValidation @ID, @UN, @PW, @ValidUser; 
    --sp_UserValidation returns 'Success' 

    If @ValidUser = 'Success' 
     Begin 
      -- 2) Validate Account 
      Execute @Current = sp_ValidateCurrent @ID, @Current; 
      --sp_ValidateCurrent returns 'Account is current' 

      If @ACurrent = 'Account is current' 
       Begin 
        Set @Message = 'Success'; 
       End 
      Else 
       Begin 
        If @Current = 'Grace' 
         Begin 
          Set @Message = 'Grace'; 
         End 
        Else 
         Begin 
          If @AccountCurrent = 'Not Billing' 
           Begin 
            Set @Message = 'Success'; 
           End 
          Else Set @Message = 'Failure' 
         End 
       End 
     End 
    Else Set @Message = 'Not valid.'; 

    Select @Message; 
END 

按照我的逻辑，@message应该等于“成功”，但“不是有效的”被退回。我究竟做错了什么？请告诉我。谢谢。

这里是sp_UserValidation逻辑：

ALTER PROCEDURE [dbo].[sp_UserValidation] 
-- Add the parameters for the stored procedure here 
@ID int, 
@UN nvarchar(30), 
@PW nvarchar(30), 
@Output nvarchar(50) out 
AS 
BEGIN 

SET NOCOUNT ON; 
Declare @UserCount int = 0; 
Declare @AccountLocked bit = 1; 
Declare @FailedAttempts int = 4; 
Declare @MaxAttempts int = 3; 
Declare @LastLogin datetime2; 

Set @Output = 'Error: Please try again'; 

-- 1) Check that Account Code/UserName/Password combination exists 
Select @UserCount = count(*) from tblUSER where ID = @AID AND UserName = @UN AND Password = @PW; 

If @UserCount = 1 
Begin 
    -- 2) Check that the User Account is not locked 
    -- 2.a) Get maximum allowed attempts 
    Select @MaxAttempts = Value from tbl_sysTABLE where Title = 'MaxUserAttempts'; 

    -- 2.b) Get total failed attempts since last successful login 
      -- Get Last Successful login date 
    Select @LastLogin = LoginDatetime from tblLOG where ID = @ID AND UserName = @UN AND LoginDatetime in (select max(LoginDatetime) from tblLOG where ID = @ID AND UserName = @UN AND Message = 'Success'); 

      -- Get failed attempts count 
    Select @FailedAttempts = count(*) from tblLOG where LoginDatetime > @LastLogin; 

    -- 2.c) If failed attempts > maximum allowed attempts, account is locked, else account is not locked. 
    If @FailedAttempts < @MaxAttempts 
    Begin 
     Set @Output = 'Success'; 
    End 
    Else Set @Output = 'User account is locked.'; 
End 

Select @Output; 
END 

Answer 1

我猜测你想要的：

Execute sp_UserValidation @ID, @UN, @PW, @ValidUser output; 

存储过程不返回字符串。

Here是返回值是整数的引用。我很惊讶它不会在写入时产生语法错误。我想这是因为return也用于可以返回任何类型的函数。

我一直使用返回作为状态指示器。在你的情况下，你传递一个变量然后使用它，所以它是一个输出参数是有道理的。