Question

Is there a way automatically update some tuples based on time.
I have a field that I would like to increment every week from the time stored for that particular row.
Say I have two tuples with date and count fields:
2000-01-02 10
2000-01-03 1

Is it possible to automatically increment the count field every week from the stored date?
So that the first row is incremented on 2000-01-09 and the second row is incremented on 2000-01-10 and this would be done weekly.

Or in general can I update something automatically based on some time gone by?

Thank you.

Answer 1

You could store an extra field: next_increment_date.

Then you update regularly (say, once per hour or day… or however often makes sense):

UPDATE my_table
  SET next_increment_date = DATE_ADD( next_increment_date, INTERVAL 1 WEEK ),
      count = count + 1
  WHERE next_increment_date <= NOW();