Question

I have wondered for a while now how to this. If I want to take weekly backups of all or many of my tables that stores values that changes every day in mysql. I also want to execute daily functions with php that update update values in my db.

I was thinking of making a stock investing function. Where I have fictional data as the value for various stocks, a value that changes randomly every day for every stock.

Maybe something like this for the last 9 days of the stock price curve.

CREATE TABLE `stocks` (
  `id` int(11) NOT NULL auto_increment,
  `name` varchar(40) NOT NULL default '', 

  `day_1` varchar(40) NOT NULL default '', 
  `day_2` varchar(40) NOT NULL default '',  
  `day_3` varchar(40) NOT NULL default '', 
  `day_4` varchar(40) NOT NULL default '', 
  `day_5` varchar(40) NOT NULL default '',  
  `day_6` varchar(40) NOT NULL default '', 
  `day_7` varchar(40) NOT NULL default '', 
  `day_8` varchar(40) NOT NULL default '', 
  `day_9` varchar(40) NOT NULL default '', 

if I could execute a php function once a day that made an array of the last 9 days of values. Then just change the day_1 value and use array_push($array, "new_stock_price"); then update the db with the new last_9_days values.

Answer 1

On a *nix system, use a CRON job. On Windows, it’s Scheduled Task… Either will execute a script at a given time on any (or a specific) day.

I’d recommend a better table design:

DROP TABLE IF EXISTS `example`.`stocks`;
CREATE TABLE  `example`.`stocks` (
  `id` int(10) unsigned NOT NULL auto_increment,
  `name` varchar(45) NOT NULL default '',
  `stock_value` varchar(40) NOT NULL default '',
  `created_date` datetime NOT NULL default CURRENT_TIMESTAMP,
  PRIMARY KEY  (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

This way, if you want to see the last 9 values for a given stock name, use:

  SELECT s.name,
         s.value,
         s.created_date
    FROM STOCKS s
   WHERE s.name = ?
ORDER BY s.created_date DESC
   LIMIT 9