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SQL Server DATEDIFF() Function

❮ SQL Server Functions

Example

Return the difference between two date values, in years:

SELECT DATEDIFF(year, '2017/08/25', '2011/08/25') AS DateDiff;
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Definition and Usage

The DATEDIFF() function returns the difference between two dates.

Syntax

DATEDIFF(interval, date1, date2)

Parameter Values

Parameter Description
interval Required. The part to return. Can be one of the following values:
  • year, yyyy, yy = Year
  • quarter, qq, q = Quarter
  • month, mm, m = month
  • dayofyear = Day of the year
  • day, dy, y = Day
  • week, ww, wk = Week
  • weekday, dw, w = Weekday
  • hour, hh = hour
  • minute, mi, n = Minute
  • second, ss, s = Second
  • millisecond, ms = Millisecond
date1, date2 Required. The two dates to calculate the difference between

Technical Details

Works in: SQL Server (starting with 2008), Azure SQL Database, Azure SQL Data Warehouse, Parallel Data Warehouse

More Examples

Example

Return the difference between two date values, in months:

SELECT DATEDIFF(month, '2017/08/25', '2011/08/25') AS DateDiff;
Try it Yourself »

Example

Return the difference between two date values, in hours:

SELECT DATEDIFF(hour, '2017/08/25 07:00', '2017/08/25 12:45') AS DateDiff;
Try it Yourself »

❮ SQL Server Functions