Fastest way of bulk update query in golang

How can I execute a bulk update query in Golang? For example I want to execute these queries in one query.

update product set product_name='AAAA' where product_id='1'

update product set product_name='BBB' where product_id='2'

update product set product_name='CCC' where product_id='3'

update product set product_name='DDDD' where product_id='4'