Question

我正在尝试设置此SQL语句，当查询计数为null或空白时，该语句将返回零值。

SELECT NAME,
       CASE
         WHEN COUNT(question1) IS NULL THEN 0
         ELSE COUNT(question1)
       END
FROM   INQUIRY2
GROUP  BY name,
          question1
HAVING Question1 = 'Yes'
       AND Name IN ( 'person1', 'person2' )

Answer 1

您正在寻找COALESCE，它会在其参数列表中返回第一个非空值。

SELECT NAME, coalesce (COUNT(question1), 0)
FROM INQUIRY2
group by name, question1
having Question1 ='Yes' 
and Name IN ('person1', 'person2')

在这种情况下，似乎COUNT（问题1）可能无效。

结果为null或空白时返回零的SQL语句

1 个答案: