Wordpress - Custom Table Column Sortable by Taxonomy Query
To achieve adding a custom sortable column to the WP_List_Table
of your post type within the WordPress administration back-end dashboard, you will need to do the following:
- Replace all occurrences of
YOUR-POST-TYPE-NAME
with your actual post type name. - Replace all occurrences of
YOUR-TAXONOMY-NAME
with your actual taxonomy name. - Replace all occurrences of
YOUR COLUMN NAME
with your actual column name. - Replace all occurrences of
YOUR-COLUMN-SLUG
with your actual column slug.
Step 1
Add Additional WordPress Admin Table Columns
if(!function_exists('mbe_change_table_column_titles')){
function mbe_change_table_column_titles($columns){
unset($columns['date']);// temporarily remove, to have custom column before date column
$columns['YOUR-COLUMN-SLUG'] = 'YOUR COLUMN NAME';
$columns['date'] = 'Date';// readd the date column
return $columns;
}
add_filter('manage_YOUR-POST-TYPE-NAME_posts_columns', 'mbe_change_table_column_titles');
}
Step 2
Add All Assigned Linkable Taxonomy Terms as Row Data Within Custom WordPress Admin Table Column
if(!function_exists('mbe_change_column_rows')){
function mbe_change_column_rows($column_name, $post_id){
if($column_name == 'YOUR-COLUMN-SLUG'){
echo get_the_term_list($post_id, 'YOUR-TAXONOMY-NAME', '', ', ', '').PHP_EOL;
}
}
add_action('manage_YOUR-POST-TYPE-NAME_posts_custom_column', 'mbe_change_column_rows', 10, 2);
}
Step 3
Enable Custom WordPress Admin Table Column to Become Sortable
if(!function_exists('mbe_change_sortable_columns')){
function mbe_change_sortable_columns($columns){
$columns['YOUR-COLUMN-SLUG'] = 'YOUR-COLUMN-SLUG';
return $columns;
}
add_filter('manage_edit-YOUR-POST-TYPE-NAME_sortable_columns', 'mbe_change_sortable_columns');
}
Step 4
Modify post_clauses
to Allow Sorting Custom WordPress Admin Table Columns by a Taxonomy Term
if(!function_exists('mbe_sort_custom_column')){
function mbe_sort_custom_column($clauses, $wp_query){
global $wpdb;
if(isset($wp_query->query['orderby']) && $wp_query->query['orderby'] == 'YOUR-COLUMN-SLUG'){
$clauses['join'] .= <<<SQL
LEFT OUTER JOIN {$wpdb->term_relationships} ON {$wpdb->posts}.ID={$wpdb->term_relationships}.object_id
LEFT OUTER JOIN {$wpdb->term_taxonomy} USING (term_taxonomy_id)
LEFT OUTER JOIN {$wpdb->terms} USING (term_id)
SQL;
$clauses['where'] .= "AND (taxonomy = 'YOUR-TAXONOMY-NAME' OR taxonomy IS NULL)";
$clauses['groupby'] = "object_id";
$clauses['orderby'] = "GROUP_CONCAT({$wpdb->terms}.name ORDER BY name ASC)";
if(strtoupper($wp_query->get('order')) == 'ASC'){
$clauses['orderby'] .= 'ASC';
} else{
$clauses['orderby'] .= 'DESC';
}
}
return $clauses;
}
add_filter('posts_clauses', 'mbe_sort_custom_column', 10, 2);
}
Step 5 (BONUS)
Adjust the Width of Custom WordPress Admin Table Columns
if(!function_exists('mbe_print_admin_styles')){
function mbe_print_admin_styles(){
if(!is_admin()){
return false;
}
global $pagenow;
if($pagenow == 'edit.php' && isset($_GET['post_type']) && $_GET['post_type'] == 'YOUR-POST-TYPE-NAME'){
echo '
<style type="text/css">
.column-YOUR-COLUMN-SLUG{
width: 10%;
}
</style>
'.PHP_EOL;
}
}
add_action('wp_print_scripts', 'mbe_print_admin_styles');
}
Thanks to @goto10
for asking Sortable admin columns, when data isn't coming from post_meta and @scribu
for posting Custom Sortable Columns and Sortable Taxonomy Columns for this answer to the original question Custom Table Column Sortable by Taxonomy Query.