I have 1 master table that contains the data fetched from the join of other 3 tables. Those three tables are updated very frequently.I want to schedule a cron job that will change only those rows That were updated in those three tables.
One way is to delete the master table and populate it again by running the sql query. But that is not efficient when I have to run the cronjob every 15 minutes and the number of rows in tables are in hundreds of thousands.
P.S. I am using php,mysql and cronjobs