Question

I want to convert the date I fetched from the database, which is generated via CURRENT_TIMESTAMP and stored in a timestamp column type, from GMT+8 to GMT+1.

$time = "2012-11-07 15:05:26"; // fetch from database
$date = new DateTime($time, new DateTimeZone('Europe/Berlin'));
echo $date->format('Y-m-d H:i:s');

However this will yield an output of “2012-11-07 15:05:26”, which I’m pretty sure is wrong.

What could be I’m missing in here?

Answer 1

First, you need to instantiate the datetime object with the original timezone. Then, after the datetime object is instantiated, adjust the timezone with DateTime::setTimezone().

See this code, where I’ve used Asia/Hong_Kong as an example GMT+8 timezone:

$time = "2012-11-07 15:05:26"; // fetch from database
$date = new DateTime($time,new DateTimeZone('Asia/Hong_Kong'));
$date->setTimezone(new DateTimeZone('Europe/Berlin'));
echo $date->format('Y-m-d H:i:s'); // yields 2012-11-07 08:05:26

If all the original dates are always consistently meant as GMT+8, and your PHP application is set to use GMT+8 as well (set with date_default_timezone_set(), for instance), there’s no need to pass the initial DateTimeZone object, as newly created DateTime objects will automatically be created with that timezone.