JOIN子句[supfrie] [复制链接]

SELECT customer_info.firstname, customer_info.lastname, purchases.item

FROM customer_info, purchases

WHERE customer_info.customer_number = purchases.customer_number;


换成
jion

SELECT customer_info.firstname, customer_info.lastname, purchases.item

FROM customer_info INNER JOIN purchases

ON customer_info.customer_number = purchases.customer_number;