oracle quiz3

http://www.oracleclub.com/article/52177

with cal as

(

select '1900' + level - 1 as year

from   dual

connect by level <= 400

)

select year, mod(year, 4), mod(year, 100), mod(year, 400), 

       decode(0, mod(year,400), 'Y', mod(year, 100), 'N', mod(year, 4), 'Y', 'N') syear

from   cal

;