t=request.form("year"

&"-"&request.form("month"

&"-"&request.form("day"

&" 00:00:00"
t1=request.form("year1"

&"-"&request.form("month1"

&"-"&request.form("day1"

&" 23:59:59"
if ……then
……
else
if request.form("year"

<>"" then
…………
else
t1=request("t1"

t=request("t"

end if
t=cdate(t)
t1=cdate(t1)
if t1<>"" then
sql0=sql0&" and ([date] between "&t&" and "&t1&" )"
end if