new high low volume date
10 15 5 11 2007-1-2 11:08:01
14 25 1 8 2007-1-2 11:08:08
14 15 5 11 2007-1-2 11:08:10
......//有上百万条记录，我只要取每天的一些数据（按天来分组）
1：我要选出每天date值最小的那条记录上的new值，volume值，以及date值
2：我要选出每天date值最大的那条记录上的new值，volume值，以及date值
3：我要选出每天low值最小的那条记录上的low值，volume值，以及date值
4：我要选出每天high值最大的那条记录上的high值，volume值，以及date值
用一条语句实现实现上面的四个功能应该怎么写？（按天分组）
如果按月分组呢？
------解决方案--------------------------------------------------------
Select new, volume, date From TableName Where date In (Select Min(date) From TableName Group By Year(date)*10000 + Month(date) * 100 * Day(date))
------解决方案--------------------------------------------------------
Select new, volume, date From TableName Where date In (Select Min(date) From TableName Group By Year(date)*10000 + Month(date) * 100 * Day(date))
union
Select new, volume, date From TableName Where date In (Select max(date) From TableName Group By Year(date)*10000 + Month(date) * 100 * Day(date))
union
Select new, volume, date From TableName Where low In (Select min(low ) From TableName Group By Year(date)*10000 + Month(date) * 100 * Day(date))
union
Select new, volume, date From TableName Where high In (Select max(high ) From TableName Group By Year(date)*10000 + Month(date) * 100 * Day(date))
------解决方案--------------------------------------------------------
Group By Year(date)*10000 + Month(date) * 100 * Day(date))
Group By 我到现在还没研究明白