distinct(columns, order_by)
public
SELECT DISTINCT clause for a given set of columns
and a given ORDER BY clause. Both PostgreSQL and Oracle overrides this for
custom DISTINCT syntax.
distinct("posts.id", "posts.created_at desc")
# File activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb, line 502
def distinct(columns, order_by)
"DISTINCT #{columns}"
end