Show the First Post from Each of 3 Different Post Types on a Web Page?

Question

I have 3 different custom post types: 1.) "events", 2.) "winners" and 3.) "offers". How would I go about retrieving the first (latest) post in each of these post types on a single web page (i.e a home page).

Would I use get_posts() or would I have to manipulate the_loop()?

Answer 1

Yes, get_posts is the safest way to use multiple loops. It does not mess up with the original query.

Another way would be to create new WP_Query objects:

$my_query = new WP_Query($args);
while ($my_query->have_posts()) : $my_query->the_post();

Note: Why you should not use query_posts()

Answer 2

Hi @dotty:

The answer from @sorich87 is correct, but I thought I'd elaborate a bit. I've coded a class for you called (verbosely) LatestPostPerPostTypeQuery and you can use it in the loop in place of WP_Query, like so:

<ul>
<?php $args = array('post_type'=>'events,winners,offers'); ?>
<?php $query = new LatestPostPerPostTypeQuery($args); ?>
<?php while($query->have_posts()): $query->the_post(); ?>
  <li><?php the_title(); ?></li>
<?php endwhile; ?>
</ul>

Below is the code for the LatestPostPerPostTypeQuery class which you can copy into your theme's functions.php file (or use the code in a plugin if you like.) The nice thing about this alternative to WP_Query is it does a single query to the database instead of one for each of the three post types like you'd be forced to use when using WP_Query() directly.

<?php
class LatestPostPerPostTypeQuery extends WP_Query {
  var $flag;
  function __construct($args=array()) {
    $this->LatestPostPerPostTypeQuery($args);
  }
  function LatestPostPerPostTypeQuery($args=array()) {
    if (isset($args['post_type']) && !is_array($args['post_type']))
      $args['post_type'] = explode(',',$args['post_type']);
    $this->flag = true;
    parent::query($args);
  }
  static function on_load() {
    add_filter('posts_join',array(__CLASS__,'posts_join'),10,2);
  }
  static function posts_join($join,$query) {
    if (isset($query->flag)) {
      global $wpdb;
      $join .=<<<SQL
INNER JOIN (
SELECT post_type,MAX(post_date) AS post_date
FROM {$wpdb->posts}
GROUP BY post_type) max_date ON 
  max_date.post_type={$wpdb->posts}.post_type AND 
  max_date.post_date={$wpdb->posts}.post_date
SQL;
    }
    return $join;
  }
}
LatestPostPerPostTypeQuery::on_load();

I've also posted a standalone file on Gist allowing you grab the source code and drop the example into a file in the root of your website to call it directly from the browser to watch it in action:

• latest-post-per-post-type-query.php