sql - グループ化による 1 つの SQL クエリでの複数のカウント

Question

年と月でグループ化されたオープン インシデントとクローズ インシデントの数を取得するクエリを実行したいのですが、以下のクエリはグループ化なしで正常に機能しますが、グループを追加すると機能しません!

SELECT (SELECT COUNT(*) AS Opened FROM Incidents) AS Total 
       (SELECT COUNT(*) AS Solved FROM Incidents WHERE (MONTH(Closedate)=MONTH(Opendate))) AS Solved
GROUP BY YEAR(Incidents.Opendate)

Answer 1

CASE式で単一のSELECTステートメントを使用できます

SELECT YEAR(Incidents.Opendate) AS [Year], 
       MONTH(Incidents.Opendate) AS [Month], 
       COUNT(*) AS Total,
       SUM(CASE WHEN MONTH(Closedate) = MONTH(Opendate) THEN 1 ELSE 0 END) AS Solved
FROM Incidents
GROUP BY YEAR(Incidents.Opendate), MONTH(Incidents.Opendate)

Answer 2

試す：

SELECT 
        (SELECT COUNT(*) FROM Incidents) as Total ,
        (SELECT COUNT(*)  FROM Incidents WHERE (Month(Closedate)=MONTH(Opendate))) as Solved
    FROM Incidents
    Group by YEAR(Incidents.Opendate)

Answer 3

私はそれを解決することができました、以下はクエリです

select  COUNT(CASE WHEN Month(Closedate)=Month(Opendate) then 1 else null end) AS closed,COUNT(*) AS Opened
from incidents
Group by Year(Opendate), Month(Opendate)
Order by Year(Opendate), Month(Opendate)