Help using Modulo Arithmetic Operator

[aspengal]

I wanna calculate the Leap year and I have this

declare @which_year numeric(4,0)

if(@which_year%4) = 0
--is a lear year
else
--not a leap year

this wont work as it gives datatype error....help pls....

 

[hmckillop]

A year will always be an int value, you need this for the modulo, so change your declaration to be this type and it will be ok.

declare @which_year int --numeric(4,0)

if(@which_year%4) = 0
--is a lear year
else
--not a leap year

"I'm living so far beyond my income that we may almost be said to be living apart

 

[earthandfire]

Just because a year divides exactly by 4 does not make it a leap year.

If a year is a century year it must divide by 400 to be a leap year. (1900 was not a leap year but 2000 was)

 

[vongrunt]

Dirty way:

select isdate (convert(varchar(4), @year) + '0229')

------
heisenbug: A bug that disappears or alters its behavior when one attempts to probe or isolate it
schroedinbug: A bug that doesn't appear until someone reads source code and realizes it never should have worked, at which point the program promptly stops working for everybody until fixed.
[ba

 

[earthandfire]

vongrunt, I like your cheat

 

[vongrunt]

Older - lazier . A month ago I would probably suggest this:

if @year % 4 = 0 and (@year % 100 <> 0 or @year % 400 = 0)
-- is a leap year
else
--not a leap year

... and year ago:

select 1 - (sign(@year % 4) | (~sign(@year % 100) & sign(@year % 400)))

I don't even wanna think about five years ago... brrrr.

------
heisenbug: A bug that disappears or alters its behavior when one attempts to probe or isolate it
schroedinbug: A bug that doesn't appear until someone reads source code and realizes it never should have worked, at which point the program promptly stops working for everybody until fixed.
[ba

 

[earthandfire]

 

[aspengal]

Thanks a lot for all the responses!