Error SQL:

SELECT `id`, `parent` FROM `ctim_ru_cat` WHERE `id` =
MYSQL Error:
You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near '' at line 1

stack trace:
#0  sql->query(SELECT `id`, `parent` FROM `ctim_ru_cat` WHERE `id` = ) called at [/home/admin/web/]
#1  sql->fetch_one(SELECT `id`, `parent` FROM `ctim_ru_cat` WHERE `id` = ) called at [/home/admin/web/]
#2  getCategoryParent() called at [/home/admin/web/]
#3  getCategoriesByParent() called at [/home/admin/web/]
#4  require_once(/home/admin/web/ called at [/home/admin/web/]