little help in Time Difference!!

[okha]

Hi,
When user visits the site his visit_time and visit_date is stored in the database, What I want is to delete the visitor details after completetion of 24 hours.. for example..
if user visit_time=23:00 and visit_date=9 March 2006
then the record will be deleted when
date=10 March 2006 and time=23:00 (24 hours completed)

This will be done via cron job (which will run every day at mid night)

Thanx for help in advance....

[PHP John]

So, what is the question?

[clamcrusher]

also, is visit_time stored as a timestamp? or as a string representation of a date?
hope its a timestamp, will make things much easier.

[okha]

At the moment i have time formats in string... here is the code

<?php
//get current server time
require_once("db.php");
$current_time = date("H:i:s");
$current_date = date("j F Y");
$ip=$_SERVER['REMOTE_ADDR'];
$q="DELETE from visitor where  '$current_date'>visit_date" AND what codtion to put here for time(24 hours);

$result = mysql_query($q,$status)or die("no match found")

[PHP John]

Is it too late to change the times you have in the database to a timestamp? As ClamCrusher has said, it's easier to work with timestamps, as you can test in this manner:

is the current timestamp 86400 or more greater than the timestamp in the database

if($databaseTimestamp + 86400 < $currentTimestamp)
{
delete
}

[clamcrusher]

yeah if you had timestamps in your db you could just do the update in a single sql statement

since its in string format, your going to need to loop through your records 1 by 1, take the date string, convert it to a timestamp, then you can:

if($databaseTimestamp + 86400 < $currentTimestamp)
{
delete
}

fortunately, strtotime() will probably make short work of converting your strings to timestamps.

its a very good practice to store dates as timestamps.

[okha]

ok one little question regarding that condition

if($databaseTimestamp + 86400 < $currentTimestamp)
{
delete
}
why we add 86400 here? 

thanx

[PHP John]

Timestamps are recorded in seconds. 86400 is the number of seconds in 24 hours.

[okha]

Okies ...
thanx for your help friends...