sqlÓïÑÔ

select *from customers
 
select *from orders
 
select customers.cust_id, orders.order_num  from customers inner join orders on customers.cust_id=orders.cust_id
 
select customers.cust_id, orders.order_num  from customers left outer join orders on customers.cust_id=orders.cust_id
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select customers.cust_id,count(orders.order_num) as num_ord from customers inner join orders on customers.cust_id = orders.cust_id group by customers.cust_id
select customers.cust_id,count(orders.order_num) as num_ord from customers left outer join orders on customers.cust_id = orders.cust_id group by customers.cust_id