複雑なケース・ステートメントの問題 - Oracle SQL

Question

以下の問合せを書き込みましたが、集計はケース・ステートメントの前に行う必要があるため、これを構造化する最良の方法についてのアドバイスが大好きです。

Select Store, CUSTID, CUST.ID_CUST, 

Sum(
    CASE 
    WHEN Cust_Gift.Code_Status = 'C' AND Gift_Item.FLAG_STORE_LOC = 'N' 
    THEN Cust_Gift.AMT_PAID ELSE 0 
    END) GiftAmt, 

Sum(
    CASE WHEN Cust_Gift.Code_Status = 'C' AND Gift_Item.FLAG_STORE_LOC = 'Y' 
    THEN Cust_Gift.AMT ELSE 0 
    END) CustGiftAmt, 

Sum(
    CASE WHEN Cust_Coupon.Code_Status = 'C' 
    THEN Cust_Coupon.AMT 
    ELSE 0 
    END) CouponAmt, 

Sum(CASE WHEN Cust_Sports.Status = 'C' 
    THEN Cust_Sports.AMT 
    ELSE 0 
END) SportsAmt 

FROM CUST 
    LEFT OUTER JOIN CUST_GIFT 
    ON CUST.ID_CUST = CUST_GIFT.ID_CUST 
    LEFT OUTER JOIN CUST_COUPON 
    ON CUST.ID_CUST = CUST_COUPON.ID_CUST 
    LEFT OUTER JOIN CUST_SPORTS 
    ON CUST.ID_CUST = CUST_SPORTS.ID_CUST 
    INNER JOIN GIFT_ITEM 
    ON CUST_GIFT.ID_GIFT_ITEM = GIFT_ITEM.ID_GIFT_ITEM 

WHERE (STORE = 'M669098' OR STORE = 'M66923434') 

Group by CustID, Store, CUST.ID_CUST 

Answer 1

これは、あなたがそれを行うことができ一つの方法である：

SELECT cust.store, 
     cust.custid, 
     cust.id_cust, 
     gift.giftamt, 
     gift.custgift, 
     cpn.couponamt, 
     sprt.sportsamt 
FROM cust 
     LEFT OUTER JOIN (SELECT id_cust, 
           SUM(CASE WHEN cg.code_status = 'C' AND gi.flag_store_loc = 'N' THEN cg.amt_paid END) giftamt, 
           SUM(CASE WHEN cg.code_status = 'C' AND gi.flag_store_loc = 'Y' THEN cg.amt_paid END) custgiftamt 
         FROM cust_gift cg 
           INNER JOIN gift_item gi ON cg.id_gift_item = gi.id_gift_item) gift ON cust.id_cust = gift.id_cust 
     LEFT OUTER JOIN (SELECT id_cust, 
           SUM(CASE WHEN code_status = 'C' THEN amt END) couponamt 
         FROM cust_coupon) cpn ON cust.id_cust = cpn.id_cust 
     LEFT OUTER JOIN (SELECT id_cust, 
           SUM(CASE WHEN status = 'C' THEN amt END) sportsamt 
         FROM cust_sports) sprt ON cust.id_cust = sprt.id_cust 
WHERE (STORE = 'M669098' OR STORE = 'M66923434');