Calculating Age in Years, Months and Days in SQL Server 2012

In this article, I would like to show the difference between two dates in years, months and days in SQL Server. In this article, we take an existing date and the current date and using the "GetDate" function to find the years, months and days. The "DATEDIFF" and "Datepart" functions are used to determine years, months and days between two dates. So let's have a look at a practical example of how to calculate age in SQL Server 2012. The example is developed in SQL Server 2012 using the SQL Server Management Studio. 

 

First of all, we will see the use of the "DATEDIFF" and "Datepart" functions.

 

The DATEDIFF Function

 

The SQL Server "DATEDIFF" Function is used to calculate the difference between two dates. 

 

Syntax

 

The syntax of the "DATEDIFF" built-in date function is as follows:

 

DATEDIFF(Datepart, Startdate, Enddate)

 

Here, The "Datepart" parameter is the part of the datetime to calculate the difference of. The Datepart can be any of the following:

 

Ms - Milliseconds

Yy - Year

Qq - Quarter of the Year

Mm - Month

Dy - The Day of the Year

Dd - Day of the Month

Wk - Week

Dw - The Day of the Week

Hh - Hour

Mi - Minute

Ss - Second

 

DATEDIFF Example

Declare @dateofbirth datetime
Declare @currentdatetime datetime
Declare @years varchar(4)
set @dateofbirth = '1986-03-15' --Birthdate
set @currentdatetime  = getdate() --Current Datetime
select @years = datediff(year,@dateofbirth,@currentdatetime)
select @years   + ' years,' as years

Output

 

 

The Datepart Function

 

The SQL Server "Datepart" function returns a portion of a SQL Server Datetime field.

 

Syntax

  

The syntax of the "Datepart" built-in date function is as follows :

 

DATEPART ([Date part], [Datetime])

 

Here, the <Date part> parameter is the part of the datetime. Datetime is the name of a SQL Server Datetime field and portion is one of the following:

 

Ms - Milliseconds

Yy - Year

Qq - Quarter of the Year

Mm - Month

Dy - The Day of the Year

Dd - Day of the Month

Wk - Week

Dw - The Day of the Week

Hh - Hour

Mi - Minute

Ss - Second

 

DATEPART Example

Declare@dateofbirthdatetime
Declare@currentdatetimedatetime
Declare@daysvarchar(3)
set@dateofbirth='1986-03-15'--Birthdate
set@currentdatetime =getdate()--Current Datetime
select@days=datepart(d,@currentdatetime)-datepart(d,@dateofbirth)
select @days   +' days' asDays

Output

 

 

Calculating Age in years, months and days

 

Here is an example to get the years, months and days between two dates.

Declare@dateofbirthdatetime
Declare@currentdatetimedatetime
Declare@yearsvarchar(40)
Declare@monthsvarchar(30)
Declare@daysvarchar(30)
set@dateofbirth='1986-03-15'--birthdate
set@currentdatetime =getdate()--current datetime
select@years=datediff(year,@dateofbirth,@currentdatetime)-- To find Years
select@months=datediff(month,@dateofbirth,@currentdatetime)-(datediff(year,@dateofbirth,@currentdatetime)*12)
-- To Find Months
select@days=datepart(d,@currentdatetime)-datepart(d,@dateofbirth)-- To Find Days
select@years  +' years,   ' +@months +' months,   '+@days   +' days' asYearMonthDay

Output