如何使用 GROUP BY 從 JOIN 更新

在SELECT查詢

SELECT b.id, MIN(IFNULL(a.views,0)) AS counted 
FROM table1 a JOIN table2 b ON a.id=b.id GROUP BY id 
HAVING counted>0

如何將此查詢轉換UPDATE為

UPDATE b.number = counted

UPDATE table2 AS b1, ( SELECT b.id, MIN(IFNULL(a.views, 0)) AS counted 
                      FROM table1 a 
                      JOIN table2 b ON a.id = b.id 
                      GROUP BY id 
                      HAVING counted > 0 ) AS b2
SET b1.number = b2.counted
WHERE b1.id = b2.id

   UPDATE table2
   INNER JOIN (SELECT MIN(IFNULL(table1.views,0)) counted
   FROM table1
   GROUP BY table1.id
   HAVING counted>0
   ) x ON x.id = table2.id
   SET table2.number = x.counted

引用自：https://dba.stackexchange.com/questions/218762