(select Max(DAYear+DAMonth+DADay+DAHour+DAMinute) as AA from T_DataByTen where DataNo = 'A550101'
Group By (DAYear+DAMonth+DADay+DAHour+DAMinute),DataNo);为什么这条“Max”语句,返回的是三条记录???
Group By (DAYear+DAMonth+DADay+DAHour+DAMinute),DataNo);为什么这条“Max”语句,返回的是三条记录???
(select Max(DAYear+DAMonth+DADay+DAHour+DAMinute) as AA from T_DataByTen where DataNo = 'A550101'
Group By DataNo);
“group by (DAYear+DAMonth+DADay+DAHour+DAMinute),DataNo”为什么要去掉呢???去掉就好了
是的,Max(DAYear+DAMonth+DADay+DAHour+DAMinute),应该按照其它字段分组才对的。
先这样查下试试,看是几条数据