count the time difference?

[mshen]

I am working with PHP and MySQL.

I set up a account and save the set-up time to database.I only hope the account available on 48 hrs.I hope to check how long the accout set-up.

Please let me know how to check the time difference.

Thanks a lot.

[jpmoriarty]

on your set up script enter a value into the database:

mktime();

then in your script take that value from the database (lets call it $set_up) and do something like this:

$hours = 48;
$time_diff = mktime() - $set_up;
if($time_diff>($hours*60*60))
{
  // then the account was made over 48 hours ago
}
else
{
  // then it was made in the last 48 hours
}

[drew010]

Depending on how you store the register date (as timestamp or actual date with or without time) will affect how to select this difference. Look at http://www.mysql.com/doc/en/Date_and_time_functions.html. Specifically check the DATE_SUB function as that will subtract a given number of days from the date you give.

In my following examples, the dates are stored simply in yyyy-mm-dd format
For example :
SELECT userid, registerdate FROM user WHERE registerdate < DATE_SUB(curdate(), INTERVAL 2 DAY);
will select all accounts older than 2 days.
so you might throw an additional and clause to make it select accounts older than 2 days but younger than a week or something.

I hope that helps a little.