drop table dw_access_info;
create table dw_access_info(remote_addr string,firt_req_time string,last_req_time string,stay_long string)
partitioned by(prtflag_day string);
insert into table dw_access_info partition(prtflag_day='19/Sep/2013')
select remote_addr,firt_req_time,last_req_time,
case stay_long
when 0 then 30000
else stay_long
end as stay_long
from ods_access_info
where prtflag_day='18/Sep/2013';