سلام استاد
وقتی میخوام گروه حذف کنم از parenid ایراد میگیره
SqlException: The DELETE statement conflicted with the SAME TABLE REFERENCE constraint "FK_CourseGroups_CourseGroups_ParentId". The conflict occurred in database "TattolearnCore_DB", table "dbo.CourseGroups", column 'ParentId'.
The statement has been terminated.
مخصوص اعضای ویژه 
