How to change the MySQL timezone

AA-00339

How to Change MySQL Timezone for Your Website

Overview

When developing your website, you may need to compare a certain date/time with the current date/time on the server. Understanding how to work with different timezones in MySQL is essential for accurate date and time handling in your applications.

Important Information About Server Timezone

The timezone on iFastNet servers is set to EDT (Eastern Daylight Time). This is a global server setting that cannot be changed at the user level.

However, you can use an easy workaround if you need to work with a different timezone by modifying how MySQL returns date and time values.

Solution: Using MySQL Date Functions

Standard Current Date/Time Query

The most common query for selecting the current date/time is:

SELECT NOW();

This will return the current server time in EDT timezone.

Adding Time to Current Date/Time

If you want to add time to the result (for example, to convert to a timezone that's ahead of EDT), you can use the DATE_ADD function.

Example: Adding 2 hours to the current time

SELECT DATE_ADD(NOW(), INTERVAL 2 HOUR);

Subtracting Time from Current Date/Time

If you want to subtract time from the server timezone (for example, to convert to a timezone that's behind EDT), you can use the DATE_SUB function.

Example: Subtracting 2 hours from the current time

SELECT DATE_SUB(NOW(), INTERVAL 2 HOUR);

Practical Examples

Converting to Different Timezones

Here are some common timezone conversions from EDT:

Pacific Time (PDT) - 3 hours behind EDT:

SELECT DATE_SUB(NOW(), INTERVAL 3 HOUR) AS pacific_time;

Central European Time (CET) - 6 hours ahead of EDT:

SELECT DATE_ADD(NOW(), INTERVAL 6 HOUR) AS european_time;

UTC/GMT - 4 hours behind EDT during daylight saving:

SELECT DATE_SUB(NOW(), INTERVAL 4 HOUR) AS utc_time;

Using in Your Application

You can incorporate these functions directly into your application queries:

Example: Finding records created today in Pacific timezone

SELECT * FROM your_table 
WHERE DATE(created_at) = DATE(DATE_SUB(NOW(), INTERVAL 3 HOUR));

Example: Inserting a timestamp in a specific timezone

INSERT INTO your_table (event_time, description) 
VALUES (DATE_ADD(NOW(), INTERVAL 2 HOUR), 'Event in timezone +2');

Flexible Time Adjustments

Using DATE_SUB and DATE_ADD, you can modify query results to fit your specific timezone needs:

  • INTERVAL 1 MINUTE - for minute adjustments
  • INTERVAL 1 HOUR - for hour adjustments
  • INTERVAL 1 DAY - for day adjustments
  • INTERVAL 1 WEEK - for week adjustments

Important Notes

Daylight Saving Time Considerations

Remember that EDT (Eastern Daylight Time) is used during daylight saving periods. During standard time periods, the server uses EST (Eastern Standard Time). You may need to adjust your calculations accordingly depending on the time of year.

Application-Level Timezone Handling

While this method works for simple timezone conversions, for complex applications, consider handling timezone conversions at the application level using your programming language's timezone libraries for more accurate results.

Testing Your Timezone Adjustments

Access Your Database

You can test these queries through several methods:

Option A: Through cPanel phpMyAdmin

  1. Go to https://ifastnet.com/portal/clientarea.php
  2. Log in with your hosting credentials
  3. Access your hosting cPanel
  4. Open phpMyAdmin from the Databases section

Option B: Direct cPanel Access

  1. Go to https://yourdomain.com/cpanel (replace with your actual domain)
  2. Log in with your cPanel credentials
  3. Open phpMyAdmin

Test Query

Run this test query to see different timezone results:

SELECT 
    NOW() as server_time_edt,
    DATE_SUB(NOW(), INTERVAL 3 HOUR) as pacific_time,
    DATE_ADD(NOW(), INTERVAL 6 HOUR) as european_time;

Need Additional Help?

If you need assistance with timezone calculations or have questions about your specific use case:

  1. Go to https://support.ifastnet.com/login.php
  2. If this is your first time accessing support, you'll need to register for a support account
  3. Once logged in, create a new support ticket describing your timezone requirements
  4. Include details about your target timezone and any specific calculations you need help with

Summary

While you cannot change the server's EDT timezone setting, you can easily work with different timezones by using MySQL's DATE_ADD and DATE_SUB functions to adjust the NOW() function results. This approach allows you to handle timezone conversions directly in your SQL queries for accurate date and time comparisons in your website applications.