Merging results of 2 WP_Query

merging_wp_queries.php

<?php

/**
 * Case: related news
 *
 * At first query for posts of same category, then, if it doesn't find enough posts, query for other posts and merge the 2 results.
 * 
 * Put the following code inside a single template.
 * 
 * @link Inspired by http://wordpress.stackexchange.com/questions/71576/combining-queries-with-different-arguments-per-post-type#answer-71582
 */
 
// First query: latest 3 posts of same category
$args = array(
  'post_type'      => 'post',
  'posts_per_page' => 3,
  'category__in'   => wp_get_post_categories( $post->ID ),
  'post__not_in'   => array( $post->ID ),
);
$my_query = new WP_Query( $args );

// Less than 3 posts? Query for more posts of any categories
if ( $my_query->post_count < 3 ) {

	$related_ids = array_map( function( $v ) {
		return $v->ID;
	}, $my_query->posts );

	$args = array(
		'post_type'      => 'post',
		'posts_per_page' => 3 - $my_query->post_count,
		'post__not_in'   => array_merge( array( $post->ID ), $related_ids ),
	);

	$more_query = new WP_Query( $args );

	$my_query->posts = array_merge( $my_query->posts, $more_query->posts );

	$my_query->post_count = count( $my_query->posts );
}


if ( $my_query->have_posts()) :
  while ( $my_query->have_posts() ) : $my_query->the_post();  ?>

        <?php the_title(); ?><br />

  <?php  endwhile; 
  endif;
wp_reset_postdata(); 

Not exactly what I needed, but let me see how I needed to merge the two queries, and it worked. Thanks for the gist.

Thank you very much. Thats what i needed

Thank you so much. Exactly the starter I needed to knock out a component of a project.