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POusing multiple mysql query loop inside each other
 

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  1. POusing multiple mysql query loop inside each other
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    <p>i have a big trouble using multiple queries inside each other. and i searched for it but could not find what i needed! so this is my problem. plz help me.</p> <p>i have a table named "cat" and i get the titles by mysql and it's ok. i have an other table named works that has a field named "Cat_ID" this is the field that connect's the data of both tables. works table has another field named "Years" and it's the year of the production of artwork.</p> <p>cat >> { ID , Title , ... } works >> { ID , Title , URL , Year , Cat_ID , ... }</p> <p>i need to categorize the gallery of works by year, so i made a code like this:</p> <pre><code>&lt;?php $result = q("cat"); while($row = mysqli_fetch_array($result)) { ?&gt; &lt;div&gt; &lt;h2&gt;&lt;a href="artwork.php?id=&lt;?php echo $row['ID'] ?&gt;"&gt; &lt;?php echo $row['Title']; ?&gt;&lt;/a&gt;&lt;/h2&gt; &lt;span&gt; &lt;?php $sql = "SELECT DISTINCT Year FROM works WHERE Cat=".$row['Cat_ID']; $yresult = mysql_query($sql); while ($yrow = mysql_fetch_row($yresult)) { //and print it as anchor here but it wont get into loop at all! } ?&gt; &lt;/span&gt; &lt;/div&gt; &lt;?php } ?&gt; </code></pre> <p>the q() is a function that just connects to DB and run the query. this line works pretty well. but the it wont enter to the inner while at all! i checked and saw that the $yrow is totally empty(by EMPTY() of php)! what can i do about it? it seems that mysql can not execute the second query at all! the solution must be in two ways i think. 1. make mysql to execute the second query. 2. change the first query in the way that get's the years distinctly and read them by mysql_fetch_array and put the years as anchor via for each.</p> <p>plz help me.</p>
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    1. USBabakslt
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    1. COThis would be a lot more efficient if you could do a join on your two SQL queries
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      1. POusing multiple mysql query loop inside each other
      1. USMark Baker
    2. COAre you sure your queries are correct and working? What does `mysql_error` show?
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      1. USandrewsi
    3. COsql shows no err it just simply returns nothing at all!
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      1. USBabakslt
 

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