Question

I have a table called log where I store the everything that the user does. what I want to do, is to run a script after showing the last 100 results.

so basically, when the admin visits the log page, he/she will see the last 100 results. while showing the last 100 results I want to delete anything in the table log other than the last 100 results that I just showed. How can I do that? I only know of the basic code for deleting a table which is

DELETE FROM table_name
WHERE some_column = some_value 

Answer 1

With a column containing the time of record creation:

DELETE FROM log WHERE created < (SELECT created FROM (
  SELECT created FROM log ORDER BY created DESC LIMIT 100, 1
) t)