date_diff function

Applies to: check marked yes Databricks SQL check marked yes Databricks Runtime 13.3 LTS and above

Returns the difference between two timestamps measured in units. date_diff (timestamp) is a synonym for timestampdiff function.

Syntax 

date_diff(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.

Examples 

-- One second shy of a month elapsed
> SELECT date_diff(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 date_diff(MONTH, TIMESTAMP'2021-02-28 12:00:00', TIMESTAMP'2021-03-28 12:00:00');
 1

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