查询时间范围
查一个表的 time 字段 时间范围是最近7天

string sql="select * from table1 time between to_date('" + DateTime.Now.AddDays(-7).ToString() + "','yyyy-mm-dd HH24:mi:ss')  AND  to_date('" + DateTime.Now.ToString() + "','yyyy-mm-dd HH24:mi:ss')";

如果最近几周应该怎么写
[解决办法]
+ DateTime.Now.AddDays(-7*周数-(int)DateTime.Now.DayOfWeek).ToString() +
[解决办法]
用得着这么复杂吗?
string sql="select * from table1 Where datediff(dd,[time],getdate())<=7

以上是获取7天内的数据
[解决办法]
1、string sql="select * from table1 where time between to_date('2013-01-01','yyyy-mm-dd HH24:mi:ss') AND to_date('2013-12-31 23:59:59','yyyy-mm-dd HH24:mi:ss')";

2、string sql="select * from table1 where to_char(time,'yyyy')=2013";