ApsaraDB RDS:Change the time zone

Scenarios

You must change the time zone of your RDS instance in the following scenarios:

• The time zone of your RDS instance differs from the time zone of the region where your workloads run. For example, the default time zone of your RDS instance created before May 30, 2021 is SYSTEM, and you must change the time zone of the instance to match the time zone of the region where your workloads run.

• Time changes between daylight saving time (DST) and winter time occur in the US, Canada, Australia, European countries, and other countries, requiring adjustment of the standard system time. For example, when the UK switches from winter time to daylight saving time, you need to change the winter time (UTC) to daylight saving time (UTC+1).

Precautions

• After changing the time zone parameter of an RDS instance, you must restart the instance for the modification to take effect. We recommend modifying parameters during off-peak hours and ensuring your application is configured to automatically reconnect to your RDS instance.

• When the default_time_zone parameter of MySQL is set to SYSTEM, the following risks may exist:

  • Time inconsistency between the primary and secondary RDS instances

    For high-performance local disk high availability instances, the time zones of the primary and secondary MySQL nodes may be inconsistent because the operating systems of the hosts where these nodes reside have different time zones. In extreme cases, this may affect data consistency.

  • Instance performance degradation

    If your business frequently uses the TIMESTAMP field type, lock contention issues may occur due to time zone conversion, resulting in instance performance fluctuations.

  • Inconsistent interpretation of CST time zone between JDBC and MySQL

    The CST time zone has multiple meanings: MySQL interprets it as UTC+08:00 China Standard Time by default, while some JDBC versions (such as 8.0.22/23) interpret it as UTC - 6 Central Standard Time (US). When the operating system time zone is CST, data read from or written to MySQL by JDBC may not meet expectations. Typical case: The time zone CST has different meanings on MySQL Server and on conntector/j.

Change the time zone of an RDS instance in the ApsaraDB RDS console

1. Go to the Instances page. In the top navigation bar, select the region in which the RDS instance resides. Then, find the RDS instance and click the ID of the instance.

2. In the left-side navigation pane, click Parameters.

3. On the Editable Parameters tab, find the default_time_zone parameter, click Runtime Parameter Values in the column, modify the time zone value in the dialog box that appears, and then click OK.

   Note

   For the values of the default_time_zone parameter, see Time zones and UTC offsets.

4. Click Apply Changes, select a time period for the changes to take effect in the dialog box that appears, and then click OK.

   Note

   If you want to cancel the parameter modification before submitting it, click Cancel.

Change the time zone of an RDS instance by calling an API operation

Sample request

This example calls the ModifyParameter operation to change the default_time_zone parameter to +9:00.

...
// Parameter settings for API request
        ModifyParameterRequest modifyParameterRequest = ModifyParameterRequest.builder()
                .DBInstanceId("rm-bp1l94k5sw1zxxxxx")
                .parameters("{"default_time_zone":"+9:00"}")
                .forcerestart(true)
                // Request-level configuration rewrite, can set Http request parameters, etc.
                // .requestConfiguration(RequestConfiguration.create().setHttpHeaders(new HttpHeaders()))
                .build();
...

JSON format response

HTTP/1.1 200 OK
Content-Type:application/json

{
  "RequestId": "6D698793-FC2B-5FC1-A6DF-33EDAD1AD6AB"
}

Check whether the time zone of an RDS instance is changed

1. Go to the Instances page. In the top navigation bar, select the region in which the RDS instance resides. Then, find the RDS instance and click the ID of the instance.

2. In the left-side navigation pane, click Parameters.

3. On the Parameter Change History tab, check whether the modified time zone parameter value has taken effect.

   

Time zones and UTC offsets

Related API operations