[MSSQL] GROUP BY 시 특정행 값 콤마로 구분하여 합쳐 보기

FOR XML 과 STUFF 함수를 이용한 간단한 예제 ;

SELECT Name,
       Code,
       Spec,
       STUFF((SELECT ',' + CONVERT(VarChar(50) , Qty) 
       	FROM ResultTable AS B
       WHERE A.Spec = B.Spec FOR XML PATH ('')),1,1,'') AS Qty
FROM ResultTable AS A
GROUP BY Spec,Name,Code