sql - 即使日期比较失败，为什么我的代码仍执行 IF block ？

Question

表中的到期日期 = '2017-10-16' 且 ExpiryTime='12:00pm' 在我们的国家/地区 Getdate 为 '2017-10-16'，当前日期时间为 '2017-10-16 11:05:33.503 '

但是，我的代码仍然执行了不应该执行的 IF 条件。为什么？

        Declare @ExpiryDate date
        Declare @ExpiryTime varchar(10)

        Set @ExpiryDate= (Select convert(varchar(11), ExpiryDate, 106) from Works where NIT_No= @NITNo and WorkNo= @WorkNo)
        Set @ExpiryTime= (Select CAST(ExpiryTime as TIME(0)) from Works where NIT_No= @NITNo and WorkNo= @WorkNo)

        IF(CONVERT(DATETIME,CONVERT(VARCHAR,@ExpiryDate,106)+ ' ' + @ExpiryTime) <= CONVERT(datetime, GETDATE()))   
        Begin
            RAISERROR('Sorry, Expiry date and time has passed', 16, 10);
            return;
        End

Answer 1

12:00pm 按 24 小时格式转换为 00:00。如果将当前日期和中午 12:00 结合起来，您预计结果是第二天的午夜，但实际上您得到的是当天的午夜。

这应该有效:

    Declare @ExpiryDate date
    Declare @ExpiryTime varchar(10)

    Set @ExpiryDate= (Select convert(varchar(11), ExpiryDate, 106) from Works where NIT_No= @NITNo and WorkNo= @WorkNo)
    Set @ExpiryTime= (Select CAST(ExpiryTime as TIME(0)) from Works where NIT_No= @NITNo and WorkNo= @WorkNo)

    declare @dateTimeCombined datetime = dateadd(ms, datediff(ms, '00:00:00', @ExpiryTime), cast(@ExpiryDate as datetime))

    IF @dateTimeCombined <= CONVERT(datetime, GETDATE())
    Begin
        RAISERROR('Sorry, Expiry date and time has passed', 16, 10);
        return;
    End