Delete meta values for all posts - WordPress

To delete post meta, the WordPress have delete_post_meta() function. We have to specify the meta key and post id as an argument for this function.

In some situations, we have to delete meta values of all posts.

Consider that we are going to create a plugin that will store some values as meta values for WordPress posts. In such situation, when user deactivate that plugin, it is better to remove this meta values for all posts.

$to_del = array('meta_key_1', 'meta_key_2', 'meta_key_3');

$args = array(
  'post_type' => 'page',
  'posts_per_page' => -1,
  'ignore_sticky_posts' => true,
  'fields' => 'ids',
  'no_found_rows' => true
);
$q = new WP_Query($args);

if (!empty($q->posts)) {
  foreach ($q->posts as $pid) {
	foreach ($to_del as $d) {
	  delete_post_meta($pid,$d);
	}
  }
}