SQL查询时某一列不重复（先对先得）
SELECT DISTINCT OverTimeHead.ApplyNo, OverTimeList.OverTimeListId
FROM OverTimeHead INNER JOIN OverTimeList ON OverTimeHead.OverTimeHeadId = OverTimeList.OverTimeHead
我要Apply不重复

[解决办法]
SELECT DISTINCT OverTimeHead.ApplyNo
FROM OverTimeHead INNER JOIN OverTimeList ON OverTimeHead.OverTimeHeadId = OverTimeList.OverTimeHead