SQL:当NULL或为空时将值合并为一个结果

Question

我有一个SQL查询返回两列 - "标题"和"计数".当"Title"为NULL或为空('')时,我想将结果合并为一行.我怎样才能做到这一点？

这是我到目前为止:

SELECT  [Title] WHEN '' THEN 'blank' ELSE ISNULL([Title],'blank') AS [Title],
        COUNT([value]) AS [Count]
FROM ....
WHERE ....
GROUP BY [Title],[Count]

但由于Group By,它们分为两个不同的行:

Answer 1

SELECT  CASE WHEN COALESCE([Title],'') = '' THEN 'blank' 
             ELSE [Title] 
        END AS [Title],
        COUNT([value]) AS [Count]
FROM ....
WHERE ....
GROUP BY CASE WHEN COALESCE([Title],'') = '' THEN 'blank' 
              ELSE [Title] 
         END