apply_filters_ref_array( ‘posts_orderby’, string $orderby, WP_Query $query )

User Contributed Notes

1. Skip to note 4 content

   Steven Lin 5 years ago

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   Example migrated from Codex:

   Consider the following code. In tandem with a rating plugin that uses a separate database table, sorting by rating value can be achieved with posts_orderby in tandem with the post_join_paged filter.

   add_filter('posts_orderby', 'edit_posts_orderby');
   add_filter('posts_join_paged','edit_posts_join_paged');
   
   function edit_posts_join_paged($join_paged_statement) {
   	$join_paged_statement = "LEFT JOIN wp_gdsr_data_article gdsra ON gdsra.post_id = wp_posts.ID";
   	return $join_paged_statement;	
   }
   
   function edit_posts_orderby($orderby_statement) {
   	$orderby_statement = "(gdsra.user_votes_total_sum/gdsra.user_votes_count) DESC";
   	return $orderby_statement;
   }
2. Skip to note 5 content

   Steven Lin 5 years ago

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   Example migrated from Codex:

   This filter is extremely powerful – it will apply a new or updated ORDERBY to every SQL SELECT statement generated by the WP_Query class. So it’s also very easy to break WordPress functionality using this filter.

   Fortunately, the posts_orderby filter will also pass a reference to the current WP_Query instance as a second parameter. It’s good practice to always check the referenced WP_Query to ensure only the desired SQL query is being modified. This is especially true on a modern site, where in many cases more than one WP_Query is run per request.

   // Add the callback to the posts_orderby filter
   add_filter('posts_orderby', 'orderby_pages_callback', 10, 2);
   
   // The posts_orderby filter
   function orderby_pages_callback($orderby_statement, $wp_query) {
   	# Verify correct post type, or any other query variable
   	if ($wp_query->get("post_type") === "page") {
   		# In this trivial example add a reverse menu order sort
   		return "wp_posts.menu_order DESC";
   	} else {
   		# Use provided statement instead 
   		return $orderby_statement;
   	}
   }
   
   // Example WP_Query that loads all pages.
   // The above filter callback will cause these to have a reverse menu order sort
   $pages_query = new WP_Query(array(
   	"post_type" => "page"
   ));

   You can also prevent any posts_orderby callbacks from being loaded by using the suppress_filters in your own WP_Query calls:

   $pages_query = new WP_Query(array(
   	"post_type" => "page",
   	"suppress_filters" => true,  // No posts_orderby filters will be run
   ));
3. Skip to note 6 content

   Aurovrata Venet 6 years ago

   You must log in to vote on the helpfulness of this noteVote results for this note: -2You must log in to vote on the helpfulness of this note

   useful to custom rank posts on the front-end,

   add_filter('posts_orderby', 'rank_my_taxonomy_post', 10,2);
   funciton rank_my_taxonomy_post($args, $wp_query){
     //first make sure this is not an admin dashboard query.
     if(is_admin()) return $args;
     //you may also want to check if this is the main query, rather than a secondary query such as widgets or menus.
     if(!is_main_query()) return $args;
     //you can use the wp_query object to target a specific query, such a a particular category term. 
     $queriedObj = $wp_query->get_queried_object();
     if (isset($queriedObj->taxonomy) && 'category'==$queriedObj->taxonomy && isset($queriedObj->term_id) && $queriedObj->term_id = 10) {
       global $wpdb;
       $args = "{$wpdb->posts}.post_name ASC"; //order by post slug ascending.
     }     
     return $args;
   }