database - a nested query question in mysql -

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i'm trying learn nested queries in mysql , i'm stuck while selecting hotels 30 miles away city , have rooms cost 150$

i can chose rooms 30 miles away city , costs 150 query,but can't reach hotels. 

    (select id rooms cost = 150 , id in  (select r_id has_rooms name in (select name is_at l_town in  (select town location distance_from_city = 30))));    rooms +----+------+---------+ | id | cost | type    | +----+------+---------+ |  1 |  100 | kral    | |  2 |    0 | kralice | |  3 |  150 | padisah | |  4 |  150 | hop     | |  5 |  150 | boss    | +----+------+---------+  has_rooms +------+------+ | r_id | name | +------+------+ |    1 |    | |    2 | b    | |    3 | c    | |    4 |    | |    3 |    | +------+------+  is_at +------+----------+ | name | l_town   | +------+----------+ |    | istanbul | | b    | izmir    | | c    | kars     | | d    | adana    | +------+----------+   select * location; +--------------------+----------+----------------+----------+ | distance_from_city | postcode | street         | town     | +--------------------+----------+----------------+----------+ |                 30 |     null | kennedy street | istanbul | |                 35 |     null | null           | kars     | |                 40 |     null | tenesse        | izmir    | |                 50 |     null | null           | adana    | +--------------------+----------+----------------+----------+  hotel  +------+--------+ | name | rating | +------+--------+ |    |      5 | | b    |      5 | | c    |      4 | | d    |      1 | +------+--------+ 

select  h.*    hotel h join    is_at ia on      ia.name = h.name join    location l on      l.town = ia.town   exists         (         select  null            rooms r         join    has_rooms hr         on      hr.r_id = r.id           hr.name = h.name                 , r.cost = 150         )         , distance_from_city <= 30

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