我有一个表,上面列出了人们的出生日期(目前是nvarchar(25))

我如何将其转换为日期,然后以年为单位计算他们的年龄?

我的数据如下所示

ID    Name   DOB
1     John   1992-01-09 00:00:00
2     Sally  1959-05-20 00:00:00

我希望看到:

ID    Name   AGE  DOB
1     John   17   1992-01-09 00:00:00
2     Sally  50   1959-05-20 00:00:00

当前回答

我得把这个扔出去。如果您使用112样式(yyyymmdd)将日期转换为一个数字,您可以使用这样的计算…

(yyyyMMdd - yyyyMMdd) / 10000 =全年差值

declare @as_of datetime, @bday datetime;
select @as_of = '2009/10/15', @bday = '1980/4/20'

select 
    Convert(Char(8),@as_of,112),
    Convert(Char(8),@bday,112),
    0 + Convert(Char(8),@as_of,112) - Convert(Char(8),@bday,112), 
    (0 + Convert(Char(8),@as_of,112) - Convert(Char(8),@bday,112)) / 10000

输出

20091015    19800420    290595  29

其他回答

在尝试了许多方法后,这是100%的工作时间使用现代MS SQL格式函数,而不是转换为风格112。两者都可以,但这是最少的代码。

谁能找到一个日期组合不工作?我不认为有一个:)

--Set parameters, or choose from table.column instead:

DECLARE @DOB    DATE = '2000/02/29' -- If @DOB is a leap day...
       ,@ToDate DATE = '2018/03/01' --...there birthday in this calculation will be 

--0+ part tells SQL to calc the char(8) as numbers:
SELECT [Age] = (0+ FORMAT(@ToDate,'yyyyMMdd') - FORMAT(@DOB,'yyyyMMdd') ) /10000
CREATE function dbo.AgeAtDate(
    @DOB    datetime,
    @CompareDate datetime
)

returns INT
as
begin

return CASE WHEN @DOB is null
THEN 
    null
ELSE 
DateDiff(yy,@DOB, @CompareDate) 
- CASE WHEN datepart(mm,@CompareDate) > datepart(mm,@DOB) OR (datepart(mm,@CompareDate) = datepart(mm,@DOB) AND datepart(dd,@CompareDate) >= datepart(dd,@DOB))
  THEN 0 
  ELSE 1
  END
END
End

GO

试试这个

DECLARE @date datetime, @tmpdate datetime, @years int, @months int, @days int
SELECT @date = '08/16/84'

SELECT @tmpdate = @date

SELECT @years = DATEDIFF(yy, @tmpdate, GETDATE()) - CASE WHEN (MONTH(@date) > MONTH(GETDATE())) OR (MONTH(@date) = MONTH(GETDATE()) AND DAY(@date) > DAY(GETDATE())) THEN 1 ELSE 0 END
SELECT @tmpdate = DATEADD(yy, @years, @tmpdate)
SELECT @months = DATEDIFF(m, @tmpdate, GETDATE()) - CASE WHEN DAY(@date) > DAY(GETDATE()) THEN 1 ELSE 0 END
SELECT @tmpdate = DATEADD(m, @months, @tmpdate)
SELECT @days = DATEDIFF(d, @tmpdate, GETDATE())

SELECT Convert(Varchar(Max),@years)+' Years '+ Convert(Varchar(max),@months) + ' Months '+Convert(Varchar(Max), @days)+'days'

我得把这个扔出去。如果您使用112样式(yyyymmdd)将日期转换为一个数字,您可以使用这样的计算…

(yyyyMMdd - yyyyMMdd) / 10000 =全年差值

declare @as_of datetime, @bday datetime;
select @as_of = '2009/10/15', @bday = '1980/4/20'

select 
    Convert(Char(8),@as_of,112),
    Convert(Char(8),@bday,112),
    0 + Convert(Char(8),@as_of,112) - Convert(Char(8),@bday,112), 
    (0 + Convert(Char(8),@as_of,112) - Convert(Char(8),@bday,112)) / 10000

输出

20091015    19800420    290595  29
declare @birthday as datetime
set @birthday = '2000-01-01'
declare @today as datetime
set @today = GetDate()
select 
    case when ( substring(convert(varchar, @today, 112), 5,4) >= substring(convert(varchar, @birthday, 112), 5,4)  ) then
        (datepart(year,@today) - datepart(year,@birthday))
    else 
        (datepart(year,@today) - datepart(year,@birthday)) - 1
    end