Decrease a Mysql value [closed]

Automatically does not, but there are some approaches to doing this.

The simplest is to implement in the query that does the update, here is an example:

UPDATE tabela SET
    campo1 = 'Teste',
    campoData = DATE_ADD(campoData, INTERVAL -1 DAY)
WHERE
    (id = 1);

You can create a trigger or event (Trigger only occurs when an operation is triggered, type insert, delete, update) to perform this operation daily, for example:

CREATE EVENT event1
ON SCHEDULE EVERY '1' DAY
DO
-- sua operação aqui, por exemplo:
   UPDATE TABELA SET CAMPODATA = str_to_date( date_format(now(), '%Y%m%d 0200'), '%Y%m%d %H%i' ) - INTERVAL 1 DAY
END