Bellow 是我的“房间”mysql 表。(这是我在此处创建的示例表。)
我想显示低价客房,以防多间客房预订。例如:用户选择了两个房间,一个成人在第一个房间,2 个成人在第二个房间。现在我的结果应该如下
我的查询是: SELECT * FROM rooms WHERE hotel_code="100" GROUP BY Adult+child 按成本 ASC 排序
它不工作。我无法通过此查询获得预期结果。请让我知道解决方案。
试试这个:
SELECT r.*
FROM Rooms r
INNER JOIN
(
SELECT
adult, child, MIN(Cost) MinCost
FROM Rooms
WHERE hotel_code = 100
GROUP BY adult, child
) m ON r.adult = m.adult AND r.child = m.child
AND r.cost = m.mincost
ORDER BY r.id
LIMIT 2;
这会给你:
| ID | HOTEL_CODE | ROOM_TYPE | ADULT | CHILD | COST |
---------------------------------------------------------
| 2 | 100 | Single Delux | 1 | 0 | 20 |
| 3 | 100 | Twin Stadard | 2 | 0 | 25 |
用(不太可扩展的)扩展来扩展 Mahmoud 的思想......
SELECT a.*
FROM
( SELECT x.*
FROM rooms x
JOIN
( SELECT hotel_code
, adult
, child
, MIN(cost) min_cost
FROM rooms
GROUP
BY hotel_code
, adult
, child
) y
ON y.hotel_code = x.hotel_code
AND y.adult = x.adult
AND y.child = x.child
AND y.min_cost = x.cost
) a
LEFT
JOIN
( SELECT x.*
FROM rooms x
JOIN
( SELECT hotel_code
, adult
, child
, MIN(cost) min_cost
FROM rooms
GROUP
BY hotel_code
, adult
, child
) y
ON y.hotel_code = x.hotel_code
AND y.adult = x.adult
AND y.child = x.child
AND y.min_cost = x.cost
) b
ON b.hotel_code = a.hotel_code
AND b.adult = a.adult
AND b.child = a.child
AND b.cost = a.cost
AND b.id < a.id
WHERE b.id IS NULL;