How set in mysql query a variable? : <p>What i have:</p>

<pre><code>$table_name_arcticles = 'arcticles';
$arcticles_count = mysqli_query($connection, "SELECT * FROM `articles` WHERE `categories_id` ="  . $data['id']);
</code></pre>

<p>What i need, something like this:</p>

<pre><code>$table_name_arcticles = 'arcticles';
$arcticles_count = mysqli_query($connection, "SELECT * FROM $table_name_arcticles WHERE `categories_id` ="  . $data['id']);
</code></pre>
