MySQL current date and time

select * from tablename
where tablename.datefield <> '' and tablename.timefield <> ''
and ( tablename.datefield < curdate() or 
( tablename.datefield <= curdate() and tablename.timefield <= curtime() )  )
and tablename.datetime <= now()
order by ablename.datefield desc, tablename.timefield asc;

select * from tablename where tablename.datefield <> '' and tablename.timefield <> '' and ( tablename.datefield < curdate() or ( tablename.datefield <= curdate() and tablename.timefield <= curtime() ) ) and tablename.datetime <= now() order by ablename.datefield desc, tablename.timefield asc;