============================================================== * select c.customerid, c.name, o.orderid from customers c, orders o join orders on c.customerid=o.customerid; select customers.customerid, customers.name, orders.orderid from customers left join orders orders on customers.customerid=orders.customerid; ============= left join ================= p.314 left join ... on(where와 비슷한 기능) lef..