Delete taxonomy and delete all post related it

Question

I want to delete all post related on taxonomy.

for e.g whenever i delete a taxonomy from back-end all posts of that taxonomy should be deleted.

i tried below code with hook name is delete_term_taxonomy

   <?php
    add_action('delete_term_taxonomy','wp_custom_delete_taxonomy');
    function wp_custom_delete_taxonomy($tt_id) {
           global $wpdb; // add action here


        $get_term_id = $wpdb->get_results("SELECT meta_value, user_id
                                        FROM `wp_usermeta`
                                        WHERE `meta_key`='term_id'
                                        AND `meta_value` =".$tt_id."");

        $post_metattid = $get_term_id[0]->meta_value;
        $user_id = $get_term_id[0]->user_id;

        $get_post_id = get_user_meta($user_id,'post_id',true);

        $delete_all_model = $wpdb->query("DELETE p,pm,tr,d,e 
                                        FROM wp_posts as p 
                                        LEFT JOIN wp_postmeta as pm ON p.id=pm.post_id 
                                        LEFT JOIN wp_term_relationships as tr ON tr.object_id=pm.post_id 
                                        LEFT JOIN wp_term_taxonomy d ON  d.term_taxonomy_id = tr.term_taxonomy_id 
                                        LEFT JOIN wp_terms e ON  e.term_id = d.term_id 
                                        WHERE tr.term_taxonomy_id=".$tt_id."");
  }  
    ?>

it's not remove posts of taxonomy, anyone have idea regarding this.

Answer 1

First of all we need to find the posts related to our taxonomy term. Then we will delete them one by one by running a foreach loop. Try below code. I hope that will work for you-

add_action('pre_delete_term', 'the_dramatist_delete_posts_on_taxonomy_delete', 1, 1 );
function the_dramatist_delete_posts_on_taxonomy_delete( $term ) {
    $args = array(
        'post_type' => 'post', // post_type
        'tax_query' => array(
            array(
                'taxonomy' => 'post_tag', // taxonomy_name
                'field' => 'id',
                'terms' => $term
            )
        )
    );

    $posts = get_posts($args);

    foreach ( $posts as $post ){
        wp_delete_post( $post->ID, true );
    }
}