Express Pardons discusses discharges according to the Canadian Criminal Code in their blog.
6.1 (1) No record of a discharge under section 736 of the Criminal Code that is in the custody of the Commissioner or of any department or agency of the Government of Canada shall be disclosed to any person, nor shall the existence of the record or the fact of the discharge be disclosed to any person, without the prior approval of the Minister, if
(a) more than one year has elapsed since the offender was discharged absolutely; or
(b) more than three years have elapsed since the offender was discharged on the conditions prescribed in a probation order.
(2) The Commissioner [that is, the Commissioner of the RCMP] shall remove all references to a discharge under section 736 of the Criminal Code from the automated criminal conviction records retrieval system maintained by the Royal Canadian Mounted Police on the expiration of the relevant period referred to in subsection (1).