ApsaraDB RDS:Modify the time zone

Scenarios

You may need to modify the time zone of your RDS MySQL instance for the following reasons:

• The time zone of your RDS MySQL instance does not match the time zone of your business region. For example, the default time zone for RDS MySQL instances purchased before May 30, 2021, is SYSTEM. You need to change this to the time zone of your business region.

• In countries such as the United States, Canada, Australia, and Europe, you need to manually adjust the standard time when switching between daylight saving time and winter time. For example, when the United Kingdom switches from winter time to daylight saving time, you need to change the time from winter time (UTC) to daylight saving time (UTC+1).

Precautions

• Changes to the time zone parameter take effect only after you restart an instance. We recommend performing this operation during off-peak hours and ensuring that your application has an automatic reconnection mechanism.

• Setting the default_time_zone parameter to SYSTEM can pose the following risks:

  • Time inconsistency between primary and secondary nodes

    For a high-availability RDS MySQL instance that uses high-performance local disks, the operating system time zones on the primary and secondary nodes might be different. This mismatch can cause a time zone difference between the primary and secondary MySQL nodes and, in extreme cases, affect data consistency.

  • Instance performance degradation

    If your services frequently use TIMESTAMP fields, lock contention may occur due to time zone conversions, leading to fluctuations in instance performance.

  • Inconsistent CST parsing between JDBC and MySQL

    The CST time zone is ambiguous: MySQL interprets it by default as UTC+08:00 China Standard Time, whereas some JDBC versions (such as 8.0.22/23) interpret it as UTC - 6 Central Standard Time. If the time zone of the host operating system is CST, this can cause unexpected data when JDBC reads from or writes to MySQL. A typical case: The time zone CST has different meanings on MySQL Server and on conntector/j.

Modify the time zone in the 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 navigation pane on the left, click Parameters.

3. On the Modifiable Parameters tab, find the default_time_zone parameter, click Running Value, and change the time zone value in the dialog box that appears.

   Note

   For a description of the values for the default_time_zone parameter, see Time Zone and UTC Offset Reference Table.

4. Click Apply Changes. In the dialog box that appears, specify when you want the change to take effect, and then click OK.

   Note

   Before you apply the changes, you can click Cancel to discard the modifications.

Modify the time zone via API

Example request

This example shows how to call the ModifyParameter API to modify 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 is the format of the returned result.

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

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

Verify the time zone change

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 navigation pane on the left, click Parameters.

3. On the Edit History tab, verify that the new time zone parameter has taken effect.

   

Time zones and UTC offsets

FAQ

Related APIs

You can modify the value of default_time_zone by calling the ModifyParameter API.