--1
select * from test
where field1<convert(datetime,'2005-8-8')
--2
select * from test
where field2>=convert(datetime,'2005-8-8')
--3
select * from test
where field1>convert(datetime,'2005-8-8 14:20:00')
1 select * from test where convert(char(8),field1,120)<'20050808'
2 select * from test where convert(char(8),field2,120)>='20050808'
3 select * from test where field1>convert(datetime,'2005-08-08 14:20:00 000')