event age
// WP_Query arguments $args = array( 'post_type' => array( 'event' ), 'meta_query' => array( 'relation' => 'AND', array( 'key' => 'age_min', 'compare' => 'NOT EXISTS', ), array( 'key' => 'age_max', 'compare' => 'NOT EXISTS', ), ), ); // The Query $query = new WP_Query( $args );