为什么我收到此错误消息（＃1111 - 无效使用组功能）？

Question

我正在尝试从每行的last_call字段中检索TIMEDIFF，其中当前行和下一行之间的TIMEDIFF大于10分钟！ 有人可以帮忙吗？ Meybe有更好的方法吗？

我的目标是在几个数据库托管之间获得所有timediff的总和，但前提是它们不超过10分钟。

SELECT DATE_FORMAT( last_call, '%d' ) AS 'day', 

(
 SELECT TIME_TO_SEC(TIMEDIFF(MAX(cl1.last_call), MIN(cl1.last_call)))
 FROM calls AS cl1
 WHERE TIME_TO_SEC(TIMEDIFF(MAX(cl1.last_call), MIN(cl1.last_call))) > 600
  AND cl1.calling_agent=9
  AND EXTRACT(DAY FROM cl1.last_call ) = EXTRACT(DAY FROM calls.last_call )
) AS 'brake' 


FROM calls
WHERE calling_agent =9
 AND last_call > DATE_SUB( now( ) , INTERVAL 12 MONTH )
GROUP BY EXTRACT( DAY FROM last_call )