datediff (timestamp) function (Databricks SQL)

Returns the difference between two timestamps measured in units.

Syntax

datediff(unit, start, end)

unit
 { MICROSECOND |
   MILLISECOND |
   SECOND |
   MINUTE |
   HOUR |
   DAY |
   WEEK |
   MONTH |
   QUARTER |
   YEAR }

Arguments

  • unit: A unit of measure.

  • start: A starting TIMESTAMP expression.

  • end: A ending TIMESTAMP expression.

Returns

A BIGINT.

If start is greater than end the result is negative.

The function counts whole elapsed units based on UTC with a DAY being 86400 seconds.

One month is considered elapsed when the calendar month has increased and the calendar day and time is equal or greater to the start. Weeks, quarters, and years follow from that.

datediff (timestamp) is a synonym for timestampdiff function (Databricks SQL).

Examples

-- One second shy of a month elapsed
> SELECT datediff(MONTH, TIMESTAMP'2021-02-28 12:00:00', TIMESTAMP'2021-03-28 11:59:59');
 0

-- One month has passed even though its' not end of the month yet because day and time line up.
> SELECT datediff(MONTH, TIMESTAMP'2021-02-28 12:00:00', TIMESTAMP'2021-03-28 12:00:00');
 1

-- Start is greater than the end
> SELECT datediff(YEAR, DATE'2021-01-01', DATE'1900-03-28');
 -120