PolarDB:Synchronize data from PolarDB for MySQL to AnalyticDB for MySQL

Step 1: Purchase a DTS instance

Purchase a data synchronization instance. On the buy page, set the following options:

• Source Instance: PolarDB

• Target Instance: AnalyticDB for MySQL

• Synchronization Topology: One-way Synchronization

Step 2: Configure the synchronization task

1. Log on to the DTS console.

   If you are redirected to the Data Management (DMS) console, click the icon in the to switch to the previous version of the DTS console.

2. In the left-side navigation pane, click Data Synchronization.

3. At the top of the Synchronization Tasks page, select the region where the destination instance resides.

4. Find the data synchronization instance and click Configure Task in the Actions column.

5. Configure the source and destination clusters.

   Section	Parameter	Description
   N/A	Synchronization Task Name	An auto-generated name. Specify a descriptive name to identify the task. The name does not need to be unique.
   Source Instance Details	Instance Type	Set to PolarDB Instance. This value cannot be changed.
   	Instance Region	The source region you selected on the buy page. This value cannot be changed.
   	PolarDB Instance ID	The ID of the source PolarDB for MySQL cluster.
   	Database Account	The database account of the source cluster. See Required permissions.
   	Database Password	The password of the source database account.
   Destination Instance Details	Instance Type	Set to AnalyticDB. This value cannot be changed.
   	Instance Region	The destination region you selected on the buy page. This value cannot be changed.
   	Version	Select 3.0.
   	Database	The ID of the destination AnalyticDB for MySQL cluster.
   	Database Account	The account of the AnalyticDB for MySQL database. See Required permissions.
   	Database Password	The password of the destination database account.

   

6. Click Set Whitelist and Next. DTS automatically adds its server CIDR blocks to the IP address whitelist of Alibaba Cloud database instances. For self-managed databases on Elastic Compute Service (ECS) instances, DTS automatically adds its CIDR blocks to the ECS security group rules—make sure the ECS instance can connect to the database. If the database runs on multiple ECS instances, manually add DTS CIDR blocks to each instance's security group rules. For on-premises databases or databases from third-party cloud providers, manually add DTS CIDR blocks to the IP address whitelist. For details, see Add the CIDR blocks of DTS servers.

   Warning

   Adding DTS CIDR blocks to your whitelist or security group rules introduces security risks. Before proceeding, take preventive measures such as using strong credentials, restricting exposed ports, authenticating API calls, auditing whitelist and security group rules regularly, and blocking unauthorized CIDR blocks. Alternatively, connect the database to DTS using Express Connect, VPN Gateway, or Smart Access Gateway.

7. Select the synchronization policy and objects.

   Parameter	Description
   Select the initial synchronization types	Select both Initial Schema Synchronization and Initial Full Data Synchronization. After the precheck completes, DTS synchronizes the schema and data of the selected objects. This is required for subsequent incremental synchronization.
   Processing Mode In Existed Target Table	Precheck and Report Errors (default): Checks for tables with identical names in both databases. If the destination already has tables with the same names, the precheck fails and the task cannot start. To resolve naming conflicts, use the object name mapping feature. See Rename an object to be synchronized. Ignore Errors and Proceed: Skips the precheck for identical table names. If schemas match, DTS skips rows whose primary keys already exist in the destination. If schemas differ, only matching columns are synchronized, or the task fails. > Warning Selecting Ignore Errors and Proceed may cause data inconsistency.
   Merge Multi Tables	Yes: Adds a __dts_data_source column to each table to track data sources. DDL operations cannot be synchronized when this option is enabled. To merge only some source tables, create separate synchronization tasks. No (default): DDL operations can be synchronized.
   Select the operation types to be synchronized	Select the operation types based on your requirements. All types are selected by default. See Supported SQL operations.
   Select the objects to be synchronized	In the Available section, select one or more tables or databases, then click the icon to move them to the Selected section. Selecting a database synchronizes all schema changes in that database. Selecting a table synchronizes only ADD COLUMN operations on that table. Object names remain unchanged in the destination by default. To rename objects, use the object name mapping feature. See Rename an object to be synchronized.
   Rename Databases and Tables	Rename objects in the destination instance using the object name mapping feature. See Object name mapping.
   Replicate Temporary Tables When DMS Performs DDL Operations	Applies when using DMS for online DDL operations. Yes: DTS synchronizes temporary tables generated by online DDL operations. Large online DDL operations may delay synchronization. No: DTS synchronizes only the original DDL data, not temporary tables. Destination tables may be locked during this process.
   Retry Time for Failed Connections	DTS retries failed connections for 720 minutes (12 hours) by default. If DTS reconnects within the retry window, synchronization resumes. Otherwise, the task fails. Note that you are charged for the DTS instance during retries. Specify the retry time based on your business needs. You can also release the DTS instance at your earliest opportunity after the source and destination instances are released.

   

8. Click Next.

9. Specify the table type for each table to synchronize to the destination AnalyticDB for MySQL cluster.Select 3.0.

   When Initial Schema Synchronization is selected, you must specify the type, primary key column, and partition key column for each table. For details, see CREATE TABLE.

   

10. Click Precheck. DTS runs a precheck before starting the synchronization task. The task can only start after the precheck passes. If any precheck item fails, click the icon next to the failed item to view details. Fix the issue and run the precheck again. If you choose not to fix an item, ignore it and run the precheck again.

11. After the Precheck Passed message appears, close the Precheck dialog box. The synchronization task starts automatically.

12. On the Synchronization Tasks page, wait for the task state to change to Synchronizing.