Unix timestamp to days, hours, minutes - php

Question

So, I have a field in my users table named last_active which updates every time a user reloads a page. It's stored in unix timestamp.
I would like to output it like this: Last online: 4 d 18 h 19 m ago
How would one do that? Can you do it with php's date()?
Thank you.

Answer 1

You could achieve this directly in MySQL if you like:
select date_format(from_unixtime(current_timestamp - last_timestamp),
'Last online: %e days, %k hours, %i minutes, %s seconds ago.');
(current_timestamp can be replaced with unix_timestamp(now()) if you want it calculated in-place)
DATE_FORMAT allows you to have a custom string based on a specific date. If you populate its date with the difference between two timestamps, it will work as you've asked.
The above solution will only work if it's under a month; if you want days of the year, use %j. The documentation for the function shows more.

Answer 2

The simplest approach to this is to take the last_active timestamp, and the current timestamp with time(). Then subtract the last active from the current timestamp, and then you simply divide the result with the amount of seconds in a day to get difference in days, amount of seconds in an hour to get difference in hours and so on.
This approach may be slightly inaccurate in some special cases (leap years, etc.) but it should suffice for your simpler usecase

Answer 3

After finding dozens of broken or half-there solutions, I built the following function for UNIX timestamps.
You can limit the detail level ...
echo timeDiff(1350297908); will show "5 minutes, 42 seconds ago".
echo timeDiff(1350297908, 1); will just show "5 minutes ago".
function timeDiff( $from, $levels=7 ){
$now = time();
$diff = ($from > $now) ? $from - $now : $now - $from;
$status = ($from > $now) ? ' away' : ' ago';
$times = array(31536000, 2628000, 604800, 86400, 3600, 60, 1);
$words = array('year', 'month', 'week', 'day', 'hour', 'minute', 'second');
$str = array();
foreach ($times as $k=>$v){
$val = floor($diff/$v);
if ($val) {
$str[] = $val .' '. $words[$k] . ($val==1 ? '' : 's');
$levels--;
}
$diff %= $v;
if ($levels==0) break;
}
return implode(', ', $str) . $status;
}

Answer 4

I wrote this simple function when I need this kind of solution (it gets minutes as input):
function minutes_to_time($minutes)
{
$obj = "";
// extract days
$days = floor($minutes/(1440)); # Divide on the daily minutes 60 min * 24 hours
# echo "Days: " . $days;
// extract hours
$hours = floor(($minutes-($days*1440))/60);
# echo " Hours: " . $hours;
// extract left minutes
$minutes = ($minutes-($days*24*60)-($hours*60));
# echo " Minutes: " . $minutes;
if ($days > 0)
{
$obj .= $days . "d ";
}
if ($hours > 0)
{
$obj .= $hours . "h ";
}
if ($minutes >= 0)
{
$obj .= $minutes . "m ";
}
$obj .= "ago";
return $obj;
}