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    <p>there a ton of different blog post about this topic out there.</p> <p>The most valuable for me, possibly was</p> <p>Xaprb post (see section "Select the top N rows from each group" for a detailed explaination)</p> <p><a href="http://www.xaprb.com/blog/2006/12/07/how-to-select-the-firstleastmax-row-per-group-in-sql/" rel="nofollow">http://www.xaprb.com/blog/2006/12/07/how-to-select-the-firstleastmax-row-per-group-in-sql/</a></p> <p>In your case that would mean. Modelling this SQL to your needs.</p> <pre><code>select type, variety, price from fruits where ( select count(*) from fruits as f where f.type = fruits.type and f.price &lt; fruits.price ) &lt;= 2; </code></pre> <p>lets try it out</p> <pre><code>SELECT r.price, r.room_id, h.hotel_id, h.city_id FROM Hotel h INNER JOIN Room r ON h.hotel_id = r.hotel_id WHERE ( select count(*) from Room as rt where r.hotel_id = rt.hotel_id and r.price &gt; rt.price ) &lt;= 10; ORDER BY h.city_id,h.hotel_id,r.price </code></pre> <p>as you can see you make an subquery to select the count of all rooms that have a price that is lower than the current root and see if the count is less than or equal to 10. </p> <p>Observe in particular how i changed the </p> <pre><code>f.price &lt; fruits.price </code></pre> <p>to </p> <pre><code>r.price &gt; rt.price </code></pre> <p>because in the example of Xaprb he selects the N cheapest fruits</p> <p>Hope that helps.</p> <p>BTW Stackoverflow isn't for solving homework. You should learn something your self as well ;-)</p>
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    1. POten cheapest room for each city
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    1. COIt's ok to ask about homework: http://meta.stackexchange.com/questions/10811/how-to-ask-and-answer-homework-questions
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    2. CO+1 for working through a solution using a similar problem to demonstrate the technique.
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    3. COtry using query from post http://www.xaprb.com/blog/2006/12/07/how-to-select-the-firstleastmax-row-per-group-in-sql/ by can't adapt it in semle above if tow or more fruit have some price, number of result row not equal 3, increases in the number of price matches
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