在SQL Server中选择命令由值比较行的

Question

我写了一个选择查询

select COUNT(csq.PK) as 'QuestionCount' , csq.VersionID  
     from tversion as aiv 
     inner join tquestion as csq csq.VersionID=aiv.VersionID  
     group by csq.VersionID 

返回以下表格。

我要检查，如果QuestionCount不匹配的任何行。

我如何在选择查询中进行检查？

Answer 1

with cte as 
    (
    select COUNT(csq.PK) as QuestionCount , csq.VersionID  
    from tversion as aiv 
    inner join tquestion as csq csq.VersionID=aiv.VersionID  
    group by csq.VersionID 
    ) 
    select case count(distinct QuestionCount) 
       when 1 then 'No Mismatch' 
       else 'Mismatched' 
      end as result 
    from cte;  

Answer 2

方式一：

SELECT DISTINCT COUNT(csq.PK) AS 'QuestionCount' 
FROM tversion AS aiv 
INNER JOIN tquestion AS csq ON csq.VersionID = aiv.VersionID 
GROUP BY csq.VersionID 

SELECT CASE @@ROWCOUNT WHEN 1 THEN 'true' ELSE 'false' END 

另一种方式：

SELECT CASE COUNT(*) WHEN 1 THEN 'TRUE' ELSE 'FALSE' END 
FROM (
    SELECT DISTINCT COUNT(csq.PK) AS 'QuestionCount' 
    FROM tversion AS aiv 
    INNER JOIN tquestion AS csq ON csq.VersionID = aiv.VersionID 
    GROUP BY csq.VersionID 
) AS T