select current year to day -'2012-08-08' from systables where tabid=1

select current year to day - datetime(2012-08-08) year to day from table(set{1})

select 
(current year to day - datetime(2012-08-08) year to day )::interval day(3) to day
from table(set{1})

select 
(current year to second - datetime(2012-08-08) year to second )::interval day(3) to day
from table(set{1})

select 
(current year to second - datetime(2012-08-08 01:01:01) year to second )::interval day(3) to day
from table(set{1})