MYSQL：從查詢

Question

我有一個查詢更新值：

SELECT a.id, b.products_id,a.zenid 
FROM titles a, ANOTHERDATABASE.products_description b 
WHERE b.products_name = a.title 

它給

id products_id  zenid 
57 3193  0 
81 2037  0 

我真正需要的是更新zendid與products_id所以它變成了：

id products_id  zenid 
57 3193  3193 
81 2037  2037 

Answer 1

這就是你如何使用加入MySQL：

UPDATE titles a 
    INNER JOIN ANOTHERDATABASE.products_description b 
    ON b.products_name = a.title 
SET a.zenid = b.products_id 

Answer 2

update a 
set a.zenid=b.products_id 
from titles a inner join ANOTHERDATABASE.products_description b 
on b.products_name = a.title