Sidebar limiting to 10 posts?

Question

I have the following code inside my single.php page:

UPDATED CODE

 <?php if (have_posts()) : the_post();
     $post_id = get_the_ID();

 if ( is_single() ) {
         $cats =  get_the_category();
         $cat = $cats[0];
 } else {
         // category archives
         $cat = get_category( get_query_var( 'cat' ) );
 }

 $cat_id = $cat->cat_ID;
 $cat_name = $cat->name;
 $cat_slug = $cat->slug;
?>
<?php query_posts('cat='.$cat_id); ?>
   <?php if (have_posts()) : ?>    
     <div id="sidebar">
       <h3><?php echo get_cat_name($cat_id); $theCount = 0; ?></h3>
         <ul class="info-list">
           <?php while (have_posts()) : the_post(); $theCount += 1; echo 'debug>' . $theCount; ?>
             <li <?php if ($post_id == get_the_ID()) {echo 'class="active"';} ?>>
                <a href="<?php the_permalink(); ?>">
                  <span><?php the_title(); ?></span>
                </a>
             </li>
           <?php endwhile; ?>
         </ul>
     </div>
   <?php endif; ?>
<?php endif; ?>

Problem being is that it only seems to grab the last 10 posts in that category where i know i have 16 posts for that sidebar to display.

Where in the code could i find where its limiting the return values??

UPDATE

 <?php if (have_posts()) : the_post();
                            $post_id = get_the_ID();

            if ( is_single() ) {
                    $cats =  get_the_category();
                    $cat = $cats[0];
            } else {
                // category archives
                    $cat = get_category( get_query_var( 'cat' ) );
            }

            $cat_id = $cat->cat_ID;
            $cat_name = $cat->name;
            $cat_slug = $cat->slug;


                    $cat_query_args = array(
// Include posts from category with ID $cat_id
'cat' => $cat_id,
// Include all posts
'posts_per_page' => -1
);

 $cat_query = new WP_Query( $cat_query_args );


 if ( $cat_query->have_posts() ) 

 ?>
 <div id="sidebar">
    <h3><?php echo get_cat_name($cat_id); $theCount = 0; ?></h3>
    <ul class="info-list">

    <?php
    while $cat_query->have_posts() : $cat_query->the_post();

        $theCount += 1; echo 'debug>' . $theCount; 
        ?>
        <li <?php if ($post_id == get_the_ID()) {echo 'class="active"';} ?>>
            <a href="<?php the_permalink(); ?>">
                <span><?php the_title(); ?></span>
            </a>
        </li>
       <?php

endwhile; 
?>

     </ul>
 </div>
<?php

 endif;

 ?>

            <?php endif; ?>

            <?php wp_reset_query(); ?>

Answer 1

Your problem is that you're using query_posts(), when you need to be using WP_Query(). To display all posts (by ignoring pagination, use the posts_per_page parameter:

$cat_query_args = array(
    // Include posts from category with ID $cat_id
    'cat' => $cat_id,
    // Include all posts
    'posts_per_page' => -1
);

$cat_query = new WP_Query( $cat_query_args );

if ( $cat_query->have_posts() ) : 

     ?>
     <div id="sidebar">
        <h3><?php echo get_cat_name($cat_id); $theCount = 0; ?></h3>
        <ul class="info-list">

        <?php
        while ( $cat_query->have_posts() ) : $cat_query->the_post();

            $theCount += 1; echo 'debug>' . $theCount; 
            ?>
            <li <?php if ($post_id == get_the_ID()) {echo 'class="active"';} ?>>
                <a href="<?php the_permalink(); ?>">
                    <span><?php the_title(); ?></span>
                </a>
            </li>
           <?php

    endwhile; 
    ?>

         </ul>
     </div>
    <?php

endif;

// Be kind; rewind
wp_reset_postdata();

Answer 2

Use query_posts only when you are intentionally messing with the main query, which should be almost never.

Use get_posts or or create a new WP_Query object instead.

$my_posts = get_posts(
    'cat='.$cat_id, 
    'posts_per_page=50'
);

If your $cat_id is correct, that should work. Then loop over it like this (from the Codex):

$args = array( 'numberposts' => 3 );
$lastposts = get_posts( $args );
foreach($lastposts as $post) : setup_postdata($post); ?>
    <h2><a href="<?php the_permalink(); ?>"><?php the_title(); ?></a></h2>
    <?php the_content(); ?>
<?php endforeach; ?>

Or use WP_Query like (also from the Codex):

// The Query
$the_query = new WP_Query( $args );

// The Loop
while ( $the_query->have_posts() ) : $the_query->the_post();
    echo '<li>';
    the_title();
    echo '</li>';
endwhile;

Answer 3

WP codex is your best friend:

From query_posts codex page:

For example, on the homepage, you would normally see the latest 10 posts. If you want to show only 5 posts (and don't care about pagination), you can use query_posts() like so:

query_posts( 'posts_per_page=5' );