How to update table with column set NULL in codeigniter

Question

i have a problem with update column with set data to NULL, i have a table user with each one column is id_parent column, user can delete parent and can add parent, so if user have a parent, id_parent will set with user's parent id , but user can delete parent's data, so if user delete parent's data, id_parent column, will set to NULL. so how to set data to null in database not " " but NULL. here's my user table.

user

id_user | name | address | id_parent

Answer 1

use this to set null column.it will work, dont forget add false on third parameter SET on active record

$this->db->set('id_parent', 'NULL', false);