Ошибка БД

Error Number: 1242

Subquery returns more than 1 row

SELECT az_lenta_posts.post_id AS id, az_lenta_posts.post_name AS name, az_lenta_posts.post_url AS url, az_lenta_posts.post_date AS date, az_lenta_posts.post_cut AS cut, az_lenta_posts.post_content AS content, az_lenta_posts.post_gallery_id AS gallery, az_lenta_posts.post_status AS status, az_lenta.lenta_options AS options, az_lenta.lenta_name AS lenta_name, post_title AS title, post_keywords AS keywords, post_description AS description, az_pages.page_url AS page_url FROM az_lenta_posts LEFT JOIN (az_lenta) ON (az_lenta_posts.post_main_lenta = az_lenta.lenta_id) LEFT JOIN (az_pages) ON (az_lenta_posts.post_main_lenta = az_pages.page_lenta_id) WHERE az_lenta_posts.post_url = 'v_peterburge_otkriti_novie_imena_modi_2018-05-20' AND az_lenta_posts.post_status ='1' AND post_lang_id = '1' AND az_pages.page_lenta_id = (SELECT post_main_lenta FROM az_lenta_posts WHERE az_lenta_posts.post_url = 'v_peterburge_otkriti_novie_imena_modi_2018-05-20')

Filename: /home/anmy/2.anmy.z8.ru/docs/libraries/site/lenta.php

Line Number: 234