sql - Return records from a table which have a match on all records of another table -


having following 3 tables in dbms:

customer(id, name, city), product(id, name, price), orders(cust_id, prod_id, date)

what query fetches customers (if any) have ordered all products? 

select c.id customer c inner join orders o on o.cust_id = c.id inner join product p on p.id = o.prod_id group c.id having count(distinct p.id) = (select count(id) product)

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