Question

我有一个SQL查询，如果结果是Null，我正在尝试返回“0”。

到目前为止，我已经尝试过：

SELECT     NULLIF (Amountt, '0') AS count
FROM         1Table
WHERE     (Operations_Day BETWEEN @startdate AND @enddate) AND (location = @Storenumber) AND (Hour = '18')

SELECT     ISNULL(Amountt, 0) AS count
FROM         1Table
WHERE     (Operations_Day BETWEEN @startdate AND @enddate) AND (location = @Storenumber) AND (Hour = '18')

SELECT CASE WHEN (Amountt IS NULL) THEN 0 ELSE Amountt END AS count
FROM         1Table
WHERE     (Operations_Day BETWEEN @startdate AND @enddate) AND (location = @Storenumber) AND (Hour = '18')

所有结果都返回一个BLANK字符串，在VB.net中处理不好如何返回“0”

Answer 1

这意味着Amountt不是NULL。请尝试使用case代替：

select (case when Amountt is null or Amountt = 'NULL' or Amountt = '' then 0 else Amountt end)

如果情况是您的代码返回 no 行，那么您可以使用聚合：

SELECT COALESCE(SUM(Amountt), '0') AS count
FROM 1Table
WHERE (Operations_Day BETWEEN @startdate AND @enddate) AND
     (location = @Storenumber) AND (Hour = '18');

ISNull，NULLIF，COALESCE，不工作

1 个答案: