sql - 根据条件用另一个表的列更新列值

Question

我有两张 table ...

table1 (id, item, price) 值:

id | item | price
-------------
10 | book | 20  
20 | copy | 30   
30 | pen  | 10

....table2 (id, item, price) 值:

id | item | price
-------------
10 | book | 20
20 | book | 30

现在我想:

update table1 
   set table1.Price = table2.price 
 where table1.id = table2.id
   and table1.item = table2.item.

我该怎么做？

Answer 1

应该这样做:

UPDATE table1 
   SET table1.Price = table2.price 
   FROM table1  INNER JOIN  table2 ON table1.id = table2.id

你也可以试试这个:

UPDATE table1 
   SET price=(SELECT price FROM table2 WHERE table1.id=table2.id);