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POMysql returns null for rows that doesn't exist
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  1. POMysql returns null for rows that doesn't exist
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    copied!<p>I have the following code:</p> <pre><code>while ($row = mysql_fetch_array($result)){ $que ='select SUM(price) from prices_adverts where advert_id="7" and room_type_id="54" and (date &gt;= "2013-09-20" AND date &lt;"2013-09-21") order by price'; $que ='select SUM(price) from prices_adverts where advert_id="7" and room_type_id="55" and (date &gt;= "2013-09-20" AND date &lt;"2013-09-21") order by price'; and etc $res=mysql_query($que) or die(); $rw=mysql_fetch_row($res); $price= $rw['0']; } </code></pre> <p>this returns sum for some records that have prices in the database and NULL for $price for the records dont exist /when a room doesnt has price for specific dates it doesn't exist in the table / So my question is how I can get result for records that exist only??? I do not need NULL values for prices and is it possible to access $price outside while ? How? Please help, thanks</p> <p>May I explain what exactly I need, this may help you to help Me :) Above I am looping hotels rooms to check how much would cost the room for specific period. Than I need to draw button outside loop which will divert visitor to reservation page. But if a hotel has no room prices available for the dates, I wish to have no button for reservation. That's why I need to figure out is there at least 1 room with prices in the hotel or not.. Hope this helps</p> ########################################################Update <p>first query: I am taking all London hotels id-s</p> <pre><code>select id from adverts where town="London" limit 0, 5 </code></pre> <p>than</p> <pre><code>for($i=0;$i&lt;$num_rows;$i++){ $row=mysql_fetch_row($result); echo echo_multy_htl_results($row[0]); } </code></pre> <p>this function echo_multy_htl_results is:</p> <pre><code>select a.article_title, a.town, a.small_image, a.plain_text, a.star_rating, a.numberrooms, rta.room_type_id, rt.bg_room_type,a.longitude, a.latitude, a.link_name, a.id from adverts a, rooms_to_adverts rta,room_types rt where a.id = rta.advert_id and rta.advert_id="3" and rta.room_type_id=rt.id and rt.occupants&gt;="1" group by rt.bg_room_type order by rt.occupants ASC </code></pre> <p>it gets info for the html hotel square and also room_types_id-s and that it comes the cod already added.. What would you suggest ?</p>
 

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