It should be noted that the results from wp_get_object_terms are not cached which will result in a db call everytime this function is called. For performance, functions like get_the_terms() (which the results of has been cached), should be used.
Логичней было бы использовать get_the_terms(), но если есть спецы по SQl, лучше пусть они напишут кастомную функцию.
