How to get difference between two dates in Years, Months and days in Sql Server

Many a time we come across a scenario where we need to calculate the difference between two dates in Years, Months and days in Sql Server. In this article we will see how we can achieve this. This article covers the following:

• Difference between two dates in Years
• Difference between two dates in Months
• Difference between two dates in Days
• Difference between two dates in X years Y Months and Z days (For example: Age in Years, Months and days)

1. Difference between two dates in Years

Approach 1:

We can use DATEDIFF() function like below to get the difference between two dates in Years in Sql Server. DATEDIFF() functions first parameter value can be year or yyyy or yy all will return the same result. Below example shows how we can get difference between two dates in Years

```DECLARE @FromDate DATETIME = '2014-12-31',
@ToDate DATETIME = '2015-01-01'
SELECT @FromDate 'From Date', @ToDate 'To Date',
DATEDIFF(YEAR, @FromDate, @ToDate)
-
(CASE
DATEDIFF(YEAR, @FromDate,@ToDate), @FromDate)
> @ToDate THEN 1
ELSE 0 END) 'Date difference in Years'
```

RESULT:

Approach 2:

You may be thinking why such a complex logic is used to calculate the difference between two dates in years in Apporach 1 instead of using just a single DATEDIFF() function. The reason for using such a complex logic is, DATEDIFF() function returns the number of boundaries crossed by the specified datepart between the specified fromdate and enddate. Basically it calculates the difference between two dates by ignoring all the dateparts smaller than the specified datepart from both the dates. Let us understand this with an example

```DECLARE @FromDate DATETIME = '2014-12-31',
@ToDate DATETIME = '2015-01-01'
SELECT @FromDate 'From Date', @ToDate 'To Date',
DATEDIFF(YEAR, @FromDate, @ToDate) 'Date difference in Years'```

RESULT:

From the above result it is clear that even-though @ToDate is the next day from the @FromDate, but still the difference returned is 1 year. So based on the need use the appropriate approach. If we need to calculate age, then we should be using the Approach1.

2. Difference between two dates in Months

We can use DATEDIFF() function like below to get the difference between two dates in Months in Sql Server. DATEDIFF() functions first parameter value can be month or mm or m all will return the same result. Below example shows how we can get difference between two dates in Months

```DECLARE @FromDate DATETIME = '2014-12-31',
@ToDate DATETIME = '2015-01-01'
SELECT @FromDate 'From Date', @ToDate 'To Date',
(DATEDIFF(MONTH, @FromDate, @ToDate)
-
DATEDIFF(MONTH, @FromDate, @ToDate), @FromDate)
> @ToDate
THEN 1 ELSE 0 END)) 'Date difference in Months'
```

RESULT:

Approach 2:

You may be thinking why such a complex logic is used to calculate the difference between two dates in months in Apporach 1 instead of using just a single DATEDIFF() function. The reason for using such a complex logic is, DATEDIFF() function returns the number of boundaries crossed by the specified datepart between the specified fromdate and enddate. Basically it calculates the difference between two dates by ignoring all the dateparts smaller than the specified datepart from both the dates. Let us understand this with an example

```DECLARE @FromDate DATETIME = '2014-12-31',
@ToDate DATETIME = '2015-01-01'
SELECT @FromDate 'From Date', @ToDate 'To Date',
DATEDIFF(MONTH, @FromDate, @ToDate) 'Date difference in Months'```

RESULT:

From the above result it is clear that even-though the @ToDate is the next day from the @FromDate, but still the difference returned is 1 Month. So based on the need use the appropriate approach.

3. Difference between two dates in Days

We can use DATEDIFF() function like below to get the difference between two dates in Years in Sql Server. DATEDIFF() functions first parameter value can be year or yyyy or yy all will return the same result. Below example shows how we can get difference between two dates in Years

```DECLARE @FromDate DATETIME = '2015-07-10 23:59:59.000',
@ToDate   DATETIME = '2015-07-11 00:00:00.000'
SELECT @FromDate 'From Date', @ToDate 'To Date',
(DATEDIFF(DAY, @FromDate, @ToDate)
-
DATEDIFF(DAY, @FromDate, @ToDate), @FromDate)
> @ToDate
THEN 1 ELSE 0 END)) 'Date difference in Days'
```

RESULT:

Approach 2:

You may be thinking why such a complex logic is used to calculate the difference between two dates in days in Apporach 1 instead of using just a single DATEDIFF() function. The reason for using such a complex logic is, DATEDIFF() function returns the number of boundaries crossed by the specified datepart between the specified fromdate and enddate. Basically it calculates the difference between two dates by ignoring all the dateparts smaller than the specified datepart from both the dates. Let us understand this with an example

```DECLARE @FromDate DATETIME = '2015-07-10 23:59:59.000',
@ToDate   DATETIME = '2015-07-11 00:00:00.000'
SELECT @FromDate 'From Date', @ToDate 'To Date',
DATEDIFF(DAY, @FromDate, @ToDate) 'Date difference in Days'```

RESULT:

From the above result it is clear that even-though the @ToDate is the next second from the @FromDate, but still the difference returned is 1 year. So based on the need use the appropriate approach.

4. Difference between two dates in X years Y Months and Z days (For example: Age in Years, Months and days)

We can use a script like below to get the difference between two dates in Years, Months and days.

```DECLARE @FromDate DATETIME = '2010-01-01 23:59:59.000',
@ToDate   DATETIME = '2015-01-02 00:00:00.000',
@Years INT, @Months INT, @Days INT, @tmpFromDate DATETIME
SET @Years = DATEDIFF(YEAR, @FromDate, @ToDate)
- (CASE WHEN DATEADD(YEAR, DATEDIFF(YEAR, @FromDate, @ToDate),
@FromDate) > @ToDate THEN 1 ELSE 0 END)

SET @tmpFromDate = DATEADD(YEAR, @Years , @FromDate)
SET @Months =  DATEDIFF(MONTH, @tmpFromDate, @ToDate)
- (CASE WHEN DATEADD(MONTH,DATEDIFF(MONTH, @tmpFromDate, @ToDate),
@tmpFromDate) > @ToDate THEN 1 ELSE 0 END)

SET @tmpFromDate = DATEADD(MONTH, @Months , @tmpFromDate)
SET @Days =  DATEDIFF(DAY, @tmpFromDate, @ToDate)
- (CASE WHEN DATEADD(DAY, DATEDIFF(DAY, @tmpFromDate, @ToDate),
@tmpFromDate) > @ToDate THEN 1 ELSE 0 END)

SELECT @FromDate FromDate, @ToDate ToDate,
@Years Years,  @Months Months, @Days Days```

RESULT:

We can wrap the above script into a scalar function like below and can be reused for calculating the difference between dates

```
CREATE FUNCTION dbo.GetDateDifference
(
@FromDate DATETIME, @ToDate DATETIME
)
RETURNS NVARCHAR(100)
AS
BEGIN
DECLARE @Years INT, @Months INT, @Days INT, @tmpFromDate DATETIME
SET @Years = DATEDIFF(YEAR, @FromDate, @ToDate)
- (CASE WHEN DATEADD(YEAR, DATEDIFF(YEAR, @FromDate, @ToDate),
@FromDate) > @ToDate THEN 1 ELSE 0 END)

SET @tmpFromDate = DATEADD(YEAR, @Years , @FromDate)
SET @Months =  DATEDIFF(MONTH, @tmpFromDate, @ToDate)
- (CASE WHEN DATEADD(MONTH,DATEDIFF(MONTH, @tmpFromDate, @ToDate),
@tmpFromDate) > @ToDate THEN 1 ELSE 0 END)

SET @tmpFromDate = DATEADD(MONTH, @Months , @tmpFromDate)
SET @Days =  DATEDIFF(DAY, @tmpFromDate, @ToDate)
- (CASE WHEN DATEADD(DAY, DATEDIFF(DAY, @tmpFromDate, @ToDate),
@tmpFromDate) > @ToDate THEN 1 ELSE 0 END)

RETURN 'Years: ' + CAST(@Years AS VARCHAR(4)) +
' Months: ' + CAST(@Months AS VARCHAR(2)) +
' Days: ' + CAST(@Days AS VARCHAR(2))
END
GO
```

Below example shows how we can use the above function in the select statement

```DECLARE @FromDate DATETIME = '2010-01-01 23:59:59.000',
@ToDate   DATETIME = '2015-01-02 00:00:00.000'
SELECT @FromDate FromDate, @ToDate ToDate,
dbo.GetDateDifference(@FromDate, @ToDate)
AS 'Difference between dates'```

RESULT:

We can as-well create a multi-statement table valued function like below to get difference between two dates in years, months and days

```CREATE FUNCTION dbo.GetDateDifferenceInYearsMonthsDays
(
@FromDate DATETIME, @ToDate DATETIME
)
RETURNS
@DateDifference TABLE (
YEAR INT,  MONTH INT, DAYS INT)
AS
BEGIN
DECLARE @Years INT, @Months INT, @Days INT, @tmpFromDate DATETIME
SET @Years = DATEDIFF(YEAR, @FromDate, @ToDate)
- (CASE WHEN DATEADD(YEAR, DATEDIFF(YEAR, @FromDate, @ToDate),
@FromDate) > @ToDate THEN 1 ELSE 0 END)

SET @tmpFromDate = DATEADD(YEAR, @Years , @FromDate)
SET @Months =  DATEDIFF(MONTH, @tmpFromDate, @ToDate)
- (CASE WHEN DATEADD(MONTH,DATEDIFF(MONTH, @tmpFromDate, @ToDate),
@tmpFromDate) > @ToDate THEN 1 ELSE 0 END)

SET @tmpFromDate = DATEADD(MONTH, @Months , @tmpFromDate)
SET @Days =  DATEDIFF(DAY, @tmpFromDate, @ToDate)
- (CASE WHEN DATEADD(DAY, DATEDIFF(DAY, @tmpFromDate, @ToDate),
@tmpFromDate) > @ToDate THEN 1 ELSE 0 END)

INSERT INTO @DateDifference
VALUES(@Years, @Months, @Days)

RETURN
END```

Below example shows how we can use the above function in the select statement

```DECLARE @FromDate DATETIME = '2010-01-01 23:59:59.000',
@ToDate   DATETIME = '2015-01-02 00:00:00.000'
SELECT *
FROM dbo.GetDateDifferenceInYearsMonthsDays(@FromDate,@ToDate)
GO```

RESULT:

11 thoughts on “How to get difference between two dates in Years, Months and days in Sql Server”

1. isk says:

2. Sankara says:

It’s really helpful. Very good article

3. mukesh says:

4. JJ says:

Using this as a reference: http://www.timeanddate.com/date/durationresult.html?d1=22&m1=05&y1=2002&d2=21&m2=06&y2=2002&ti=on

When I try to use the query from 22-May-2002 to 21-Jun-2002 (Include end date in calculation), the query is giving me 31 days as a result instead of 1 month. How can get around this? Here’s my query:

DECLARE @FromDate DATETIME = ‘2002-05-22 00:00:00.000’,
@ToDate DATETIME = ‘2002-06-21 00:00:00.000’,
@Years INT, @Months INT, @Days INT, @tmpFromDate DATETIME
SET @Years = DATEDIFF(YEAR, @FromDate, @ToDate)
– (CASE WHEN DATEADD(YEAR, DATEDIFF(YEAR, @FromDate, @ToDate),
@FromDate) > @ToDate THEN 1 ELSE 0 END)

SET @tmpFromDate = DATEADD(YEAR, @Years , @FromDate)
SET @Months = DATEDIFF(MONTH, @tmpFromDate, @ToDate)
– (CASE WHEN DATEADD(MONTH,DATEDIFF(MONTH, @tmpFromDate, @ToDate),
@tmpFromDate) > @ToDate THEN 1 ELSE 0 END)

SET @tmpFromDate = DATEADD(MONTH, @Months , @tmpFromDate)
SET @Days = 1+DATEDIFF(DAY, @tmpFromDate, @ToDate)
– (CASE WHEN DATEADD(DAY, DATEDIFF(DAY, @tmpFromDate, @ToDate),
@tmpFromDate) > @ToDate THEN 1 ELSE 0 END)

SELECT @FromDate FromDate, @ToDate ToDate,
@Years Years, @Months Months, @Days Days

5. Martin Gonzalez says:

Hello,
My friends Bienvenido, Oscar and me made some modification to the function to show only the data that has values.

SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
— =============================================
— Create date: July 10, 2015
— Description: Get difference between two dates in Years, Months and days in Sql Server
— =============================================
— Modified by: Bienvenido Lopez, Oscar Lopez and Martin Gonzalez, from Dominican Republic
— Modified date: April 29, 2016

create FUNCTION dbo.GetDateDifference
(
@FromDate DATETIME,
@ToDate DATETIME
)
RETURNS NVARCHAR(100)
AS
BEGIN
DECLARE @Years INT
DECLARE @Months INT
DECLARE @Days INT
DECLARE @Horas INT
DECLARE @Minutos INT
DECLARE @Segundos INT
DECLARE @tmpFromDate DATETIME

SET @Years = DATEDIFF(YEAR, @FromDate, @ToDate)
– (CASE WHEN DATEADD(YEAR, DATEDIFF(YEAR, @FromDate, @ToDate),
@FromDate) > @ToDate THEN 1 ELSE 0 END)

SET @tmpFromDate = DATEADD(YEAR, @Years , @FromDate)
SET @Months = DATEDIFF(MONTH, @tmpFromDate, @ToDate)
– (CASE WHEN DATEADD(MONTH,DATEDIFF(MONTH, @tmpFromDate, @ToDate),
@tmpFromDate) > @ToDate THEN 1 ELSE 0 END)

SET @tmpFromDate = DATEADD(MONTH, @Months , @tmpFromDate)
SET @Days = DATEDIFF(DAY, @tmpFromDate, @ToDate)
– (CASE WHEN DATEADD(DAY, DATEDIFF(DAY, @tmpFromDate, @ToDate),
@tmpFromDate) > @ToDate THEN 1 ELSE 0 END)

SET @tmpFromDate = DATEADD(DAY, @Days , @tmpFromDate)
SET @Horas = DATEDIFF(HOUR, @tmpFromDate, @ToDate)
– (CASE WHEN DATEADD(HOUR, DATEDIFF(HOUR, @tmpFromDate, @ToDate),
@tmpFromDate) > @ToDate THEN 1 ELSE 0 END)

SET @tmpFromDate = DATEADD(HOUR, @Horas , @tmpFromDate)
SET @Minutos = DATEDIFF(MINUTE, @tmpFromDate, @ToDate)
– (CASE WHEN DATEADD(MINUTE, DATEDIFF(MINUTE, @tmpFromDate, @ToDate),
@tmpFromDate) > @ToDate THEN 1 ELSE 0 END)

SET @tmpFromDate = DATEADD(MINUTE, @Minutos, @tmpFromDate)
SET @Segundos = DATEDIFF(SECOND, @tmpFromDate, @ToDate)
– (CASE WHEN DATEADD(SECOND, DATEDIFF(SECOND, @tmpFromDate, @ToDate),
@tmpFromDate) > @ToDate THEN 1 ELSE 0 END)

RETURN CASE WHEN @Years>0 THEN CAST(@Years AS VARCHAR(4)) + ‘ Años ‘ ELSE ” END +
CASE WHEN @Months>0 THEN CAST(@Months AS VARCHAR(2)) + ‘ Meses ‘ ELSE ” END +
CASE WHEN @Days>0 THEN CAST(@Days AS VARCHAR(2)) + ‘ Dias ‘ ELSE ” END +
CASE WHEN @Horas>0 THEN CAST(@Horas AS VARCHAR(2)) + ‘ Horas ‘ ELSE ” END +
CASE WHEN @Minutos>0 THEN CAST(@Minutos AS VARCHAR(2)) + ‘ Minutos ‘ ELSE ” END +
CASE WHEN @Segundos>0 THEN CAST(@Segundos AS VARCHAR(2)) + ‘ Segundos ‘ ELSE ” END
END

Thanks Martin Gonzalez and Team for modifying and sharing it here. Hope it will help someone. Keep sharing and helping the Sql Community…