检查闰年

Question

如何检查一年是否是闰年？

我有这个代码:

declare @year int
set @year = 1968

SELECT CASE WHEN @YEAR = <LEAPYEAR> THEN 'LEAP YEAR' ELSE 'NORMAL YEAR' END

预期结果:

LEAP YEAR

Answer 1

检查2月29日:

CASE WHEN ISDATE(CAST(@YEAR AS char(4)) + '0229') = 1 THEN 'LEAP YEAR' ELSE 'NORMAL YEAR' END

或使用以下规则

CASE WHEN (@YEAR % 4 = 0 AND @YEAR % 100 <> 0) OR @YEAR % 400 = 0 THEN 'LEAP YEAR'...

Answer 2

最有效的闰年测试：

CASE WHEN @YEAR & 3 = 0 AND (@YEAR % 25 <> 0 OR @YEAR & 15 = 0) THEN ...

改编自：http : //stackoverflow.com/a/11595914/3466415