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    <p>In this many-to-many scenario you describe, you can't avoid duplicate data in any single result set you get.</p> <p>Here's an idea. Do a separate query to build an array of category names, with their database key as the array index. </p> <pre><code>$sql = "SELECT category_id, category_name FROM Categories"; $result = mysql_query($sql); $arrCategories = array(); while ( $row = mysql_fetch_assoc($result) { $arrCategories[$row['category_id']] = $row['category_name']; } </code></pre> <p>Now, you have the names of all the categories in an array. </p> <p>When you're selecting articles, you'll have to do a separate query that pulls its category_ids from the join table. You can use a two-dimensional array to have a list of article ids and their associated categories</p> <pre><code>$arrArticleCategoryIds = array(); $result = mysql_query("SELECT * FROM articles, article_categories WHERE articles.article_id = article_categories.article_id AND articles.article_id = 1"); while ( $rows = mysql_fetch_array($result) ) { // why bother doing this when you've already hard-coded "1"? $article_id = $rows['article_id']; $article_title = $rows['article_title']; //(loop all the category_id from the 2nd table and add to the array below) // $categories_id[] .= ??????? --&gt; How do i do this? // here's how: $sql = "SELECT category_id FROM `article_categories` WHERE article_id = $article_id "; $category_id_results = mysql_query($sql); while ( $category_id_row = mysql_fetch_assoc($category_id_results) ) { $arrArticleCategoryIds[$article_id][] = $row['category_id']; } } </code></pre> <p>You'll wind up with two arrays:</p> <pre><code>$arrCategories Array ( [1] =&gt; apple [2] =&gt; banana ... ) $arrArticleCategoryIds Array ( [1] =&gt; Array ( [1] =&gt; 13 [2] =&gt; 9 ) [3] =&gt; Array ( [1] =&gt; 5 [2] =&gt; 7 ) ) ) </code></pre> <p>Where '1' and '3' are article ids, and 13, 9, 5, and 7 are category ids that belong to the article id they're found under. </p>
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    1. POSQL Query to pull records from 2 tables related to each other - Table 2 depending upon Table 1
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    1. COHi, thank you for taking time to reply. Although I do appreciate your solution, my requirement slightly varies and it's missing the primary goal I am trying to achieve, deal with everything in a single query. I did think of such similar solution as yours and in fact, I would not have to even fetch rows in a while loop for the first query, nor use the complicated syntax, if I were to use 2 separate queries. I would just need to get the article Id and loop through the categories by that. Problem solved painlessly if it's a 2 query operation. But I wanted to get everything in 1 shot.Thanks again.
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