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POWarning when calling mysqli_error()
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  1. POWarning when calling mysqli_error()
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    copied!<blockquote> <p><strong>Possible Duplicate:</strong><br> <a href="https://stackoverflow.com/questions/1654958/php-warning-help">PHP warning help?</a> </p> </blockquote> <p>I'm trying to join three tables from a database in-order to display a users selected categories but I get the following error.</p> <pre><code>Warning: mysqli_error() expects exactly 1 parameter, 0 given in </code></pre> <p>I think I'm doing something wrong when I query my database.</p> <p>Here is the code below.</p> <pre><code>// Query member data from the database and ready it for display $mysqli = new mysqli("localhost", "root", "", "sitename"); $dbc = mysqli_query($mysqli,"SELECT users.*, categories.*, users_categories.* FROM users_categories INNER JOIN users_categories ON users_categories.user_id = users.user_id JOIN categories ON users_categories.user_id = users.user_id WHERE users_categories.user_id=3"); if (!$dbc) { // There was an error...do something about it here... print mysqli_error(); } //Users entered category loop while ($row = mysqli_fetch_assoc($dbc)) { if (! empty($row['category'])) { echo '&lt;div class="skill-info"&gt;'; echo '&lt;p&gt;' , htmlspecialchars($row['category']) , '&lt;/p&gt;'; } } </code></pre> <p>Here is my MySQL tables structure.</p> <pre><code>CREATE TABLE users ( user_id INT UNSIGNED NOT NULL AUTO_INCREMENT, user_name VARCHAR(255) NOT NULL, PRIMARY KEY (user_id) ); CREATE TABLE categories ( id INT UNSIGNED NOT NULL AUTO_INCREMENT, parent_id INT UNSIGNED NOT NULL DEFAULT 0, category VARCHAR(255) NOT NULL, url VARCHAR(255) NOT NULL, PRIMARY KEY (id), INDEX parent (parent_id) ); CREATE TABLE users_categories ( id INT UNSIGNED NOT NULL AUTO_INCREMENT, user_id INT UNSIGNED NOT NULL, category_id INT UNSIGNED NOT NULL, PRIMARY KEY (id) ); </code></pre> <p>Now I get the following error</p> <pre><code>Not unique table/alias: 'users_categories' </code></pre> <p>How do I fix this?</p> <p>Thanks everyone for the help. Is there a way i can reward every one for there help here on stackoverflow instead of one person?</p>
 

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