Modify synchronization objects

Prerequisites

• The data synchronization instance must be in the Incremental Write module with a status of Running or Failed.

• To ensure that DTS can connect to the source and destination databases and read their schema information, do not perform operations such as upgrades, configuration changes, network switches, or cross-availability zone migrations on the databases while you modify the synchronization objects. The source and destination databases must remain operational.

• The latency of the data synchronization instance must be less than 10 minutes.

Notes

• You cannot modify synchronization objects if the Incremental Write module's status is not Running or Failed.

• When you add a field as a new synchronization object, DTS synchronizes only its incremental data, not its full data.

• When you add new synchronization objects, changes to Synchronization Types apply only to the new objects.

• After you add synchronization objects, DTS restarts the Incremental Data Collection module. This may cause a brief latency in the synchronization task.

• You cannot add or modify a data verification task while modifying synchronization objects.

• You can modify only databases and tables, not other object types.

• You cannot modify the Whether to Migrate Accounts setting while modifying synchronization objects.

• If your destination database is AnalyticDB for MySQL 2.0, you must perform the operation in the previous version of the console.

  Note

  In the Data Management (DMS) console, you can click the icon in the bottom-right corner, and then click the icon to return to the legacy Data Transmission Service console.

• If you synchronize objects at the table level, do not perform any DDL operation within 5 minutes before modifying the synchronization objects. Otherwise, the synchronization task reports an error.

• If the source database is SQL Server, you cannot add or remove databases when modifying synchronization objects.

• If a bidirectional synchronization instance does not have a separate conflict resolution policy configured, you cannot configure one when modifying synchronization objects.

• If you need to both add and remove synchronization objects, perform these actions in two separate operations. For example, first remove the objects and commit the change, and then add the new objects. Otherwise, the synchronization instance may encounter an error.

Steps

1. Go to the data synchronization task list page in the destination region. You can do this in one of two ways.

   DTS console

   1. Log on to the DTS console.

   2. In the navigation pane on the left, click Data Synchronization.

   3. In the upper-left corner of the page, select the region where the synchronization instance is located.

   DMS console

   Note

   The actual steps may vary depending on the mode and layout of the DMS console. For more information, see Simple mode console and Customize the layout and style of the DMS console.

   1. Log on to the DMS console.

   2. In the top menu bar, choose Data + AI > DTS (DTS) > Data Synchronization.

   3. To the right of Data Synchronization Tasks, select the region of the synchronization instance.

2. In the Actions column of the target data synchronization instance, click Reselect Objects.

3. Modify the synchronization objects.

   • Add synchronization objects

     In the Source Objects box, select the synchronization objects to add, and then click to move them to the Selected Objects box.

     Important

     • In Synchronization Types, you can select whether to synchronize the schema and full data of new objects (This applies only to new objects).

     • If you only need to use the object name mapping feature, you need to move the synchronization object from Selected Objects to Source Objects and submit the changes. Then, use the Modify Synchronization Objects feature to add the object back to Selected Objects before you use the object name mapping feature. Otherwise, the mapping will not take effect.

   • Remove synchronization objects

     In the Selected Objects box, select the synchronization object to remove, and click to move it to the Source Objects box.

4. Click Next: Advanced Settings.

5. Click Next: Precheck and Start Task.

   Note

   • After you modify the synchronization objects, the instance runs a precheck. The task can start only after the precheck passes.

   • If the precheck fails or generates a warning, fix the issue and run the precheck again.

6. When the Success Rate is 100%, click Changed. Return .

7. In the Status column, view the status of the instance after you modify the synchronization objects.

   Note

   If you have not enabled the Auto Refresh feature, you need to manually click the button above Actions to refresh the synchronization instance's Status.

FAQ

• If the destination database of a synchronization instance is Kafka, can you change the Kafka Data Compression Format?

  Yes, this is supported.

• For a synchronization instance with Kafka as the destination database, can you modify the Message acknowledgement mechanism?

  Yes, this is supported.

• Can I modify a data verification task when modifying synchronization objects?

  No, this is not supported.

• The precheck fails after I add new synchronization objects. How can I delete the added objects?

  1. Log on to the Data Transmission Service (DTS) console.

  2. In the task list, find the target task and click its task ID.

  3. In the left navigation bar, click Object Changes. On the Add an object to a data synchronization task tab, find the corresponding subtask and click Stop Task and Rollback.

• My task uses both full and incremental synchronization. How can I re-run full data synchronization for a single object?

  1. Remove the synchronization object:

     1. Click Reselect Objects in the Actions column of the target synchronization instance.

     2. In the Selected Objects box, select the synchronization object to remove, and click to move it to the Source Objects box.

     3. Click Next: Advanced Settings and Next: Precheck and Start Task.

     4. When the precheck success rate displays as 100%, click Changed. Return .

  2. Add the synchronization object back:

     Note

     Before adding the object again, delete the corresponding object in the destination database to prevent data inconsistency.

     1. In the Actions column of the target data synchronization instance, click Reselect Objects.

     2. In the Source Objects box, select the synchronization objects to add, and then click to move them to the Selected Objects box.

     3. Click Next: Advanced Settings and Next: Precheck and Start Task.

     4. When the precheck success rate is 100%, click Changed. Return .