Drupal7: Next & Prew node

Long time i had the idea to create Next & Prew links in node pages. For example to process a portfolio, or a section of the article. So today I made it.

First, you need to add this code on template.php

 function next_page_link($node){                $next_nid = db_query("
      SELECT nid FROM {node}
      WHERE created > :created AND type = :type AND status = 1
      LIMIT 1",                        
array(':created' => $node->created,':type' => $node->type))                        ->fetchObject();                if($next_nid) {                        return '/'.drupal_get_path_alias('node/'.$next_nid->nid);                }                else {                        return false;                }        }        function previous_page_link($node){                $next_nid = db_query("
      SELECT nid FROM {node}
      WHERE created < :created AND type = :type AND status = 1
      ORDER BY created DESC
      LIMIT 1",                        
array(':created' => $node->created,':type' => $node->type)) ->fetchObject();                
if($next_nid) 
{
return '/'.drupal_get_path_alias('node/'.$next_nid->nid);
}   else {                        
    return false;
}
}

Nice, now last step, add this code on node.tpl.php

<?php $next = next_page_link($node);                
   $previous = previous_page_link($node); ?>        
   <?php if($previous !== false): ?>                
     <a href="<?=$previous; ?>" class="previouslink">Prew</a>        
   <?php endif; ?>        <?php if($next !== false): ?>                
     <a href="<?=$next; ?>" class="nextlink">Next</a>        
<?php endif; ?>

So, it's all. Now you can use css for your individual design. Enjoy!