Sql Min query condition with join - mysql

Question

I'm having two tables
abserve_hotels
hotel_id name trendy
1 A 1
2 B 1
3 C 0
4 D 0
4 E 0
6 G 0
7 F 0
abserve_hotel_rooms
room_id room_prize hotel_id
1 235 1
2 500 2
3 1000 1
4 2356 7
5 800 7
Here, I'm using this following query
SELECT `h`.*,`ar`.* from `abserve_hotel_rooms` as `ar` JOIN `abserve_hotels` as `h` ON `ar`.`hotel_id` = `h`.`hotel_id` WHERE `h`.`trendy` =1 LIMIT 5
But,when I using this query will retrieve the hotel_id two times if it having two rooms in that hotel..
i.e.,
hotel_id name trendy room_id room_prize
1 A 1 1 235
1 A 1 3 1000
2 B 1 2 500
But,I need only the minimum of room_prize if the hotel_id having two rooms,
For example,
hotel_id name trendy room_id room_prize
1 A 1 1 235
2 B 1 2 500
Like this,Someone help me..

Answer 1

Use a MIN with GROUP BY will do.
SQLFiddle:
http://sqlfiddle.com/#!9/46ff3/1
SELECT `h`.*,`ar`.room_id, MIN(`ar`.room_prize) as min_room_prize
from `abserve_hotel_rooms` as `ar` JOIN `abserve_hotels` as `h` ON `ar`.`hotel_id` = `h`.`hotel_id`
WHERE `h`.`trendy` =1
group by h.hotel_id
LIMIT 5
SQLFiddle output:
hotel_id name trendy room_id min_room_prize
1 A 1 1 235
2 B 1 2 500

Answer 2

DROP TABLE IF EXISTS hotels;
CREATE TABLE hotels
(hotel_id INT NOT NULL AUTO_INCREMENT PRIMARY KEY
,name CHAR(1) NOT NULL
,trendy TINYINT NOT NULL
);
INSERT INTO hotels VALUES
(1,'A',1),
(2,'B',1),
(3,'C',0),
(4,'D',0),
(5,'E',0),
(6,'G',0),
(7,'F',0);
DROP TABLE IF EXISTS rooms;
CREATE TABLE rooms
(room_id INT NOT NULL AUTO_INCREMENT PRIMARY KEY
,room_prize INT NOT NULL
,hotel_id INT NOT NULL
);
INSERT INTO rooms VALUES
(1, 235,1),
(2, 500,2),
(3,1000,1),
(4,2356,7),
(5, 800,7);
SELECT h.*
, x.room_id
, x.room_prize
FROM hotels h
JOIN rooms x
ON x.hotel_id = h.hotel_id
JOIN
( SELECT hotel_id
, MIN(room_prize) room_prize
FROM rooms
GROUP
BY hotel_id
) y
ON y.hotel_id = x.hotel_id
AND y.room_prize = x.room_prize
WHERE h.trendy = 1
ORDER
BY h.hotel_id
LIMIT 5;
+----------+------+--------+---------+------------+
| hotel_id | name | trendy | room_id | room_prize |
+----------+------+--------+---------+------------+
| 1 | A | 1 | 1 | 235 |
| 2 | B | 1 | 2 | 500 |
+----------+------+--------+---------+------------+