我使用以下声明;
SELECT RESV_ID, BOOKING_CUS_ID, ACC_ID,
(SELECT F.FLI_PRICE FROM FLIGHT F WHERE F.FLI_ID = R.IN_FLIGHT_ID) AS DEPART_FLIGHT_PRICE,
(SELECT F1.FLI_PRICE FROM FLIGHT F1 WHERE F1.FLI_ID = R.OUT_FLIGHT_ID) AS RETURN_FLIGHT_PRICE,
(SELECT AC.ACC_PRICEPN FROM ACCOMMODATION AC WHERE AC.ACC_ID = R.ACC_ID) AS ACCOMMODATION_PRICE
FROM HOLIDAY_RESERVATION R;
产生以下结果;
RESV_ID BOOKING_CUS_ID ACC_ID DEPART_FLIGHT_PRICE RETURN_FLIGHT_PRICE ACCOMMODATION_PRICE
---------- -------------- ---------- ------------------- ------------------- -------------------
1 1 2 520 450 350
2 3 4 250 150 150
3 5 6 290 300 450
4 7 7 399 450 650
5 9 365 345
6 11 558 460
7 13 250 250
8 15 550 550
9 17 25 250
10 19 19 450
10 rows selected.
问题： 我如何总结价格字段，某些价格无法提供因为预订仅限住宿或仅限航班，因此两个值都不会一直存在，这就是问题所在< / p>
DEPART_FLIGHT_PRICE RETURN_FLIGHT_PRICE ACCOMMODATION_PRICE
此外： 我希望将这三个值的SUM插入或更新到预订表的SUBTOTAL中，也许通过使用select into或update，我花了一整天的时间尝试这样做，但我的技能有限。任何帮助将不胜感激。
航班表
FLI_ID FLI_CO FLI_AIRCRA DEPT_AIRPORT ARRV_AIRPORT DEPT_TIME ARRV_TIME FLI_PRICE
1 BD425 Boeing 707 1 12 18-MAR-12 02.24.00 AM 18-MAR-12 06.24.00 AM 520
2 LX345 Beriev 30 6 7 20-MAR-12 03.30.00 PM 20-MAR-12 04.20.00 PM 250
3 NZ4445 Boeing 720 9 14 25-MAR-12 09.00.00 AM 25-MAR-12 05.00.00 PM 290
4 TP351 Boeing 767 10 15 25-MAR-12 11.25.00 AM 25-MAR-12 03.35.00 PM 399
5 BA472 Boeing 720 5 14 26-MAR-12 01.05.00 PM 26-MAR-12 04.15.00 PM 365
住宿
ACC_ID ACC_TYPE_CODE ACC_DESC ACC_PRICEPN ACC_ROOMS RESORT_ID ACC_ADDR CITY_ID
1 1 Three bedroom bungalow near theme park 500 3 1
2 1 Two bedroom bungalow next to disney house 350 2 1
3 1 One bedroom bungalow with lake view 250 2 2
4 2 One bedroom chalet near the lake 150 1 2
5 2 Four bedroom chalet near the tree house 600 4 3
预订
RESV_ID EMP_ID BOOKING_CUS_ID RESV_DATE HOLIDAY_S HOLIDAY_E IN_FLIGHT_ID OUT_FLIGHT_ID IN_FLIGHT_SEATS_NO OUT_FLIGHT_SEATS_NO ACC_ID SUBTOTAL
1 338 1 16-FEB-12 18-MAR-12 20-APR-12 1 11 2 2 2
2 335 3 10-JAN-12 20-MAR-12 22-APR-12 2 12 2 2 4
3 338 5 05-MAR-12 25-MAR-12 26-APR-12 3 13 2 2 6
4 328 7 02-JAN-12 25-MAR-12 25-APR-12 4 14 2 2 7
5 311 9 20-JAN-12 26-MAR-12 21-APR-12 5 15 2 2
6 317 11 07-JAN-12 27-MAR-12 22-APR-12 6 16 2 2
7 344 13 29-FEB-12 15-MAR-12 12-APR-12 7 17 2 2
8 326 15 11-JAN-12 18-MAR-12 12-APR-14 8 18 2 2
9 329 17 16-JAN-12 19-MAR-12 17-APR-12 25
10 323 19 18-FEB-12 20-MAR-12 21-APR-12 19
好的，我设法得到了我想要的结果
SELECT HR.RESV_ID, F_IN.FLI_ID, F_IN.FLI_PRICE, F_OUT.FLI_ID, F_OUT.FLI_PRICE, AC.ACC_ID, AC.ACC_PRICEPN, NVL(F_IN.FLI_PRICE,0)+NVL(F_OUT.FLI_PRICE,0)+NVL(AC.ACC_PRICEPN,0) AS TOTAL
FROM HOLIDAY_RESERVATION HR
LEFT JOIN FLIGHT F_IN ON HR.IN_FLIGHT_ID = F_IN.FLI_ID
LEFT JOIN FLIGHT F_OUT ON HR.OUT_FLIGHT_ID = F_OUT.FLI_ID
LEFT JOIN ACCOMMODATION AC ON HR.ACC_ID = AC.ACC_ID
ORDER BY HR.RESV_ID;
产额
RESV_ID FLI_ID FLI_PRICE FLI_ID FLI_PRICE ACC_ID ACC_PRICEPN TOTAL
---------- ---------- ---------- ---------- ---------- ---------- ----------- ----------
1 1 500 11 555 2 350 1405
2 2 150 12 253 4 150 553
3 3 300 13 345 6 450 1095
4 4 450 14 343 7 650 1443
5 5 345 15 242 587
6 6 460 16 460 920
7 7 250 17 250 500
8 8 550 18 550 1100
9 25 250 250
10 19 450 450
以下声明是更新预订表。 感谢来自DBA stackxchange的Leigh Riffel提供以下代码
UPDATE HOLIDAY_RESERVATION R SET SUBTOTAL =
NVL((SELECT F.FLI_PRICE FROM FLIGHT F WHERE F.FLI_ID = R.IN_FLIGHT_ID), 0) +
NVL((SELECT F.FLI_PRICE FROM FLIGHT F WHERE F.FLI_ID = R.OUT_FLIGHT_ID), 0) +
NVL((SELECT AC.ACC_PRICEPN FROM ACCOMMODATION AC WHERE AC.ACC_ID = R.ACC_ID), 0);
现在，使用从上面执行的总和中获得的值填充小计＆gt;＆gt;
RESV_ID EMP_ID BOOKING_CUS_ID RESV_DATE HOLIDAY_S HOLIDAY_E IN_FLIGHT_ID OUT_FLIGHT_ID IN_FLIGHT_SEATS_NO OUT_FLIGHT_SEATS_NO ACC_ID SUBTOTAL
---------- ---------- -------------- --------- --------- --------- ------------ ------------- ------------------ ------------------- ---------- ----------
1 338 1 16-FEB-12 18-MAR-12 20-APR-12 1 11 2 2 2 1405
2 335 3 10-JAN-12 20-MAR-12 22-APR-12 2 12 2 2 4 553
3 338 5 05-MAR-12 25-MAR-12 26-APR-12 3 13 2 2 6 1095
4 328 7 02-JAN-12 25-MAR-12 25-APR-12 4 14 2 2 7 1443
5 311 9 20-JAN-12 26-MAR-12 21-APR-12 5 15 2 2 587
6 317 11 07-JAN-12 27-MAR-12 22-APR-12 6 16 2 2 920
7 344 13 29-FEB-12 15-MAR-12 12-APR-12 7 17 2 2 500
8 326 15 11-JAN-12 18-MAR-12 12-APR-14 8 18 2 2 1100
9 329 17 16-JAN-12 19-MAR-12 17-APR-12 25 250
10 323 19 18-FEB-12 20-MAR-12 21-APR-12 19 450
随后，代码被添加到触发器（这是最初的意图）
CREATE OR REPLACE TRIGGER HR_SUBTOTAL
BEFORE INSERT OR UPDATE ON HOLIDAY_RESERVATION
FOR EACH ROW
BEGIN
SELECT
NVL((SELECT F.Fli_Price FROM Flight F WHERE F.Fli_ID = :new.In_Flight_ID), 0) +
NVL((SELECT F.Fli_Price FROM Flight F WHERE F.Fli_ID = :new.Out_Flight_ID), 0) +
NVL((SELECT AC.Acc_PricePn FROM Accomodation AC WHERE AC.Acc_ID = :new.Acc_ID), 0)
INTO :new.Subtotal
FROM dual;
END;
/
答案 0 :(得分：2)
对于SUM，假设您希望将NULL值视为0，则只需要对数字NVL进行操作
NVL( DEPART_FLIGHT_PRICE, 0 ) +
NVL( RETURN_FLIGHT_PRICE, 0 ) +
NVL( ACCOMMODATION_PRICE, 0 )
至于UPDATE，听起来你只需要一个相关的UPDATE语句。
UPDATE reservation r
SET subtotal = (SELECT (SELECT NVL( DEPART_FLIGHT_PRICE, 0 ) +
NVL( RETURN_FLIGHT_PRICE, 0 ) +
NVL( ACCOMMODATION_PRICE, 0 )
FROM (SELECT RESV_ID,
BOOKING_CUS_ID,
ACC_ID,
(SELECT F.FLI_PRICE
FROM FLIGHT F
WHERE F.FLI_ID = R.IN_FLIGHT_ID) AS DEPART_FLIGHT_PRICE,
(SELECT F1.FLI_PRICE
FROM FLIGHT F1
WHERE F1.FLI_ID = R.OUT_FLIGHT_ID) AS RETURN_FLIGHT_PRICE,
(SELECT AC.ACC_PRICEPN
FROM ACCOMMODATION AC
WHERE AC.ACC_ID = R.ACC_ID) AS ACCOMMODATION_PRICE
FROM dual));
答案 1 :(得分：1)
你在问：
如何总结价格字段，因为您可以看到其中一些字段可以为空。
DEPART_FLIGHT_PRICE RETURN_FLIGHT_PRICE ACCOMMODATION_PRICE
将它们包含在NVL函数中，如下所示：
NVL(DEPART_FLIGHT_PRICE, 0)
然后将它们总结起来。
对于第二部分，您需要的是MERGE语句。一个很好的例子是http://www.oracle-developer.net/display.php?id=203