informix如何显示一年中第几天

Hero--008

RT!谢谢～

Hero--008

在网上找到了
CREATE FUNCTION day_of_year(dt date)
RETURNS integer
WITH(NOT VARIANT)
RETURN(1 + dt - MDY(1, 1, YEAR(dt)) );
END FUNCTION;

select first 1 day_of_year('20090701') day from systables;

yunzhongyue

直接
select first 1 '20090701'-mdy(01,01,year('20090701'))+1
from systables

就可以了。