將行轉換為列並計算總和

Question

我有這個

我想要這個

但我得到這個

我的查詢是

SELECT   SID, 
         NAME, 
         SUBJECT, ( 
         CASE 
                  WHEN EXAMTYPE IN ('ASSIGNMENTS', 
                                    'PRACTICAL') THEN SUM(MARKS) 
                  ELSE 0 
         END) AS "ASSIGNMENTS + PRACTICAL", ( 
         CASE 
                  WHEN EXAMTYPE = 'WRITTEN' THEN SUM(MARKS) 
                  ELSE 0 
         END) AS "WRITTEN"
FROM     MARKSHEET 
WHERE    EXAMTYPE IN ('ASSIGNMENTS', 
                      'PRACTICAL', 
                      'WRITTEN') 
GROUP BY SID, 
         NAME, 
         SUBJECT, 
         EXAMTYPE

我正在使用 IBM DB2。我將永遠感激任何/所有幫助。 謝謝！

Answer 1

您需要將 case 表達式放在 sum() 中 - 如sum(case when...)此外，從group by clause中刪除examType字段

SELECT   SID, 
         NAME, 
         SUBJECT, sum( 
         CASE 
                  WHEN EXAMTYPE IN ('ASSIGNMENTS', 
                                    'PRACTICAL') THEN MARKS 
                  ELSE 0 
         END) AS "ASSIGNMENTS + PRACTICAL", ( 
         sum(CASE 
                  WHEN EXAMTYPE = 'WRITTEN' THEN MARKS
                  ELSE 0 
         END) AS "WRITTEN"
FROM     MARKSHEET 
WHERE    EXAMTYPE IN ('ASSIGNMENTS', 'PRACTICAL', 'WRITTEN') 
GROUP BY SID, NAME, SUBJECT