Solved

PHP/MySQL timezones screwing up

Posted on 2011-03-18
5
452 Views
Last Modified: 2012-05-11
OK,

I have a problem. I'm setting up a sight that will end up holding large amounts of client data records. Because the clients can export and import their data, i have to be able to maintain session based timezones with in the site and server.

Right now my server is set to GMT. When i run the date command on the shell i see, which is correct at time of posting.

    Fri Mar 18 20:04:32 GMT 2011

Then when i do hwclock --show is gives me, again this is was correct.

    Fri 18 Mar 2011 08:06:22 PM GMT

Now when i tell php to change it's timezone to GMT-4 (since that is my timezone factoring in DST)

    date_default_timezone_set('Etc/GMT-4');
    echo date("m/d/Y g:i:s A T");

I get 03/19/2011 00:11:35 AM GMT-5 Is is totally wrong in stead of taking 5 hours away it added 5 hours.

So then I did this:

    date_default_timezone_set('Etc/GMT+4');
    echo date("m/d/Y g:i:s A T");

I got 03/18/2011 4:14:56 PM GMT+4. Which is the correct time. MySQL does the same thing. It seems like both are wanting to invert the time adjustments. Am i missing something on the settings?

0
Comment
Question by:Pyromanci
  • 2
  • 2
5 Comments
 
LVL 6

Expert Comment

by:ramelong
ID: 35169815
You may try this in order to determinate if anything else is wrong:
<?
ini_set('display_errors', 1);
error_reporting(E_ALL);
echo date("m/d/Y g:i:s A T");
?>

Open in new window

since some notices and warnings of time issues related are hidden in default error reporting configuration.

Additionally, accepted time zones are listed in http://ar.php.net/manual/en/timezones.php
0
 
LVL 5

Author Comment

by:Pyromanci
ID: 35173083
There are no errors reported.
0
 
LVL 108

Expert Comment

by:Ray Paseur
ID: 35173600
This article is kind of lengthy, but it will answer your questions about time and localization.
http://www.experts-exchange.com/Web_Development/Web_Languages-Standards/PHP/A_201-Handling-date-and-time-in-PHP-and-MySQL.html

Please read it over and then post back with a code sample showing the issue, if you still have questions.

best regards, ~Ray
0
 
LVL 5

Author Comment

by:Pyromanci
ID: 35201335
That post didn't really give me that much information that i did not know. Nor does it cover why when i tell it -5 it adds 5 and when tell it +5 it minus's 5
0
 
LVL 108

Accepted Solution

by:
Ray Paseur earned 500 total points
ID: 35202162
Please see the large red warning on the man page here, and see the comments in the User-Contributed notes:
http://php.net/manual/en/timezones.others.php

A line of code that says this explicitly defies the warning, and ignores the notes.  
date_default_timezone_set('Etc/GMT+4');

Don't do that.  Instead use one of the recommended Time Zone names.

Let me try this again... and then post back with a code sample showing the issue.  Thanks. ~Ray
0

Featured Post

Is Your Active Directory as Secure as You Think?

More than 75% of all records are compromised because of the loss or theft of a privileged credential. Experts have been exploring Active Directory infrastructure to identify key threats and establish best practices for keeping data safe. Attend this month’s webinar to learn more.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

As a database administrator, you may need to audit your table(s) to determine whether the data types are optimal for your real-world data needs.  This Article is intended to be a resource for such a task. Preface The other day, I was involved …
Developers of all skill levels should learn to use current best practices when developing websites. However many developers, new and old, fall into the trap of using deprecated features because this is what so many tutorials and books tell them to u…
Explain concepts important to validation of email addresses with regular expressions. Applies to most languages/tools that uses regular expressions. Consider email address RFCs: Look at HTML5 form input element (with type=email) regex pattern: T…
The viewer will learn how to count occurrences of each item in an array.

911 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

22 Experts available now in Live!

Get 1:1 Help Now