create table Iden(ide int, order_id int);
insert into Iden(ide,order_id) values(1,1),(2,1),(3,3),(4,2),(5,2),(6,2),(7,6);
create table Orders(order_id int, quantity int);
insert into Orders(order_id,quantity) values(1,100),(1,150),(2,250),(2,250),(2,260),(3,325),(4,444);
--select O.order_id, O.quantity from Iden I left outer join Orders O on I.order_id = O.order_id
select * from Orders;
select distinct on (I.ide) ide , O.order_id, O.quantity from Iden I left join Orders O on I.order_id = O.order_id
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