Check for 29th Feb:
CASE WHEN ISDATE(CAST(@YEAR AS char(4)) + '0229') = 1 THEN 'LEAP YEAR' ELSE 'NORMAL YEAR' END
or use the following rule
CASE WHEN (@YEAR % 4 = 0 AND @YEAR % 100 <> 0) OR @YEAR % 400 = 0 THEN 'LEAP YEAR'...
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…