Describe 주민번호7번째자리로연령구하기 here


CASE 
	WHEN RIGHT(BirthDT7,1) IN ('9','0') THEN '18' + LEFT(BirthDT7, 6)
	WHEN RIGHT(BirthDT7,1) IN ('1','2') THEN '19' + LEFT(BirthDT7, 6)
	WHEN RIGHT(BirthDT7,1) IN ('3','4') THEN '20' + LEFT(BirthDT7, 6)
	WHEN RIGHT(BirthDT7,1) IN ('5','6') THEN '19' + LEFT(BirthDT7, 6)
	WHEN RIGHT(BirthDT7,1) IN ('7','8') THEN '20' + LEFT(BirthDT7, 6)
END



declare @birth7 char(7)
set @birth7 = '7611181'

select
	datediff(yy, left(birthdt,8), getdate()-1)
+	case when right(birthdt, 4) > right(convert(char(8), getdate()-1, 112), 4) then -1 else 0 end age
,	gender
from (
	select
		case when right(@birth7,1) % 2 = 1 then '남' else '여' end gender
	,	case 
			when right(@birth7,1) in (3,4,7,8) then '20' + left(@birth7,6)
			when right(@birth7,1) in (1,2,5,6) then '19' + left(@birth7,6)
			when right(@birth7,1) in (9,0) then '18' + left(@birth7,6)
		end birthdt
) t