How to add a time interval from a given date or time value using the ADDTIME() function?

ADDTIME(time, expr) is a MySQL built-in function that adds a time interval to a given date or time value. For example:

SELECT ADDTIME('2022-12-31 23:59:59.999999', '1 1:1:1.000002');
  -- +---------------------------------------------------------+
  -- | ADDTIME('2022-12-31 23:59:59.999999', '1 1:1:1.000002') |
  -- +---------------------------------------------------------+
  -- | 2008-01-02 01:01:01.000001                              |
  -- +---------------------------------------------------------+

SELECT ADDTIME('01:00:00.999999', '02:00:00.999998');
  -- +-----------------------------------------------+
  -- | ADDTIME('01:00:00.999999', '02:00:00.999998') |
  -- +-----------------------------------------------+
  -- | 03:00:01.999997                               |
  -- +-----------------------------------------------+

Reference information of the ADDTIME() function:

ADDTIME(expr1, expr2): modtime
  Adds expr2 to expr1 and returns the result. expr1 is a time or datetime
  expression, and expr2 is a time expression.

Arguments, return value and availability:
  expr1: Required. The starting time to be added to.
  expr2: Required. The time interval to be added.
  modtime: Return value. The updated time.
  Available since MySQL 4.0.

Related MySQL functions:

• SUBTIME() - Subtracting Time

⇒ CONVERT_TZ() - Converting Time Zone

⇐ ADDDATE() - Synonym for DATE_ADD()

⇑ MySQL Functions on Date and Time

⇑⇑ MySQL Function References