＃1054 - 未知列＆＃39; val＆＃39;在＆＃39; on条款＆＃39;选择MIN（）时

Question

SELECT IF(TIME_TO_SEC(TIMEDIFF(t1.dal, NOW())) < 0,
          -TIME_TO_SEC(TIMEDIFF(t1.dal, NOW())),
          NULL
       ) AS val, t2.*
FROM test t1
JOIN 
  (SELECT prod, MIN(
                    IF(TIME_TO_SEC(TIMEDIFF(dal, NOW())) < 0,
                       -TIME_TO_SEC(TIMEDIFF(dal, NOW())),
                       NULL
                    )
                 ) AS minVal
   FROM test
   GROUP BY prod
  ) t2
ON val = minVal
AND t1.prodotto = t2.prodotto;

此查询返回＃1054 - 未知列＆＃39; val＆＃39;在条款＆＃39;。

我想要做的是选择MIN（）作为描述，但也选择相应的id。

我想获得与this问题相同的结果，但不是简单地选择MIN(Value) minVal然后与ON t.Value = t2.minVal AND t.prod = t2.prod进行比较，我添加操作MIN（IF（TIME ... ）so I have no idea how to compare then on the ON`子句，在我尝试时返回错误。