activerecord_where_assoc：使ActiveRecord在关联上执行条件

ActiveRecord哪里Assoc 使用此gem可以轻松地根据ActiveRecord（Rails）中记录的关联来进行条件。 （使用SQL的EXISTS运算符） # Find my_post's comments that were not made by an admin my_post . comments . where_assoc_not_exists ( :author , is_admin : true ) . where ( ... ) # Find every posts that have comments by an admin Post . where_assoc_exists ( [ :comments , :author ] , & :admins ) . where ( ... ) # Find my_user's posts that have at least 5 non-spam comments (not_spam is a scope on comments) my_user . posts . where_assoc_count ( 5