MySQL-輸出兩個計算字段的總和

Question

我正在嘗試將等級字段轉換為總分。 因此，例如，我有兩個字段，等級1和等級1。

我可以使用以下方法將其轉換為分數：

rank1, 
CASE WHEN rank1=1 THEN 10
            WHEN rank1=2 THEN  6
            WHEN rank1=3 THEN  3
            WHEN rank1=4 THEN  2
            WHEN rank1=5 THEN  1
                        ELSE  0 END  AS score1,
rank2, 
CASE WHEN rank=1 THEN 10
            WHEN rank2=2 THEN  6
            WHEN rank2=3 THEN  3
            WHEN rank2=4 THEN  2
            WHEN rank2=5 THEN  1
                        ELSE  0 END  AS score2,

但是，如何輸出score1 + score2的總和？

我努力了：

SUM(score1 + score2) AS TotalScore,

但是它不喜歡它作為score1和score2而不是表中的字段。

謝謝！

Answer 1

rank1, 
CASE WHEN rank1=1 THEN 10
            WHEN rank1=2 THEN  6
            WHEN rank1=3 THEN  3
            WHEN rank1=4 THEN  2
            WHEN rank1=5 THEN  1
                        ELSE  0 END  AS score1,
rank2, 
CASE WHEN rank2=1 THEN 10
            WHEN rank2=2 THEN  6
            WHEN rank2=3 THEN  3
            WHEN rank2=4 THEN  2
            WHEN rank2=5 THEN  1
                        ELSE  0 END  AS score2,
(CASE WHEN rank1=1 THEN 10
            WHEN rank1=2 THEN  6
            WHEN rank1=3 THEN  3
            WHEN rank1=4 THEN  2
            WHEN rank1=5 THEN  1
                        ELSE  0 END
+
CASE WHEN rank2=1 THEN 10
            WHEN rank2=2 THEN  6
            WHEN rank2=3 THEN  3
            WHEN rank2=4 THEN  2
            WHEN rank2=5 THEN  1
                        ELSE  0 END) as TotalScore

Answer 2

將SUM（）放在CASE語句周圍：

SUM(CASE WHEN rank1=1 THEN 10
        WHEN rank1=2 THEN  6
        WHEN rank1=3 THEN  3
        WHEN rank1=4 THEN  2
        WHEN rank1=5 THEN  1
                    ELSE  0 END)  AS score1,
.....