Я проголосовал за Мехрдада, но это тоже работает. :)
CREATE function dbo.IsLeapYear
(
@TestYear int
)
RETURNS bit
AS
BEGIN
declare @Result bit
set @Result =
cast(
case when ((@TestYear % 4 = 0) and (@testYear % 100 != 0)) or (@TestYear % 400 = 0)
then 1
else 0
end
as bit )
return @Result
END
GO
CREATE FUNCTION dbo.GetDaysInMonth
(
@TestDT datetime
)
RETURNS INT
AS
BEGIN
DECLARE @Result int
DECLARE @MonthNo int
Set @MonthNo = datepart(m,@TestDT)
Set @Result =
case @MonthNo
when 1 then 31
when 2 then
case
when dbo.IsLeapYear(datepart(yyyy,@TestDT)) = 0
then 28
else 29
end
when 3 then 31
when 4 then 30
when 5 then 31
when 6 then 30
when 7 then 31
when 8 then 31
when 9 then 30
when 10 then 31
when 11 then 30
when 12 then 31
end
RETURN @Result
END
GO
Для проверки
declare @testDT datetime;
set @testDT = '2404-feb-15';
select dbo.GetDaysInMonth(@testDT)