Trying to assign crucible review to another user from backend, but not able to. Please help

[Krishna Ponnekanti]

update cru_comment set cru_user_id = 'id_user_to_keep' where cru_user_id = 'id_user_to_delete';
update cru_comment_read_status set cru_user = 'id_user_to_keep' where cru_user = 'id_user_to_delete';
update cru_review_participant set cru_user = 'id_user_to_keep' where cru_user = 'id_user_to_delete';
update cru_review set cru_creator = 'id_user_to_keep' where cru_creator = 'id_user_to_delete';

crucible version is Version:4.4.1.

Do we need to modify any of the XML files manually?