Data Transmission Service:Migrate data from a PolarDB-X 1.0 instance to an AnalyticDB for MySQL 3.0 cluster

Source database limits

Foreign key behavior

DTS does not migrate foreign keys during schema migration. During full and incremental data migration, DTS temporarily disables foreign key constraint checks and cascade operations at the session level. If cascade updates or deletions occur on the source during this time, data inconsistency may result.

Other limits

Other precautions

DTS periodically writes to the dts_health_check.ha_health_check table in the source database to advance the binlog position. This is expected behavior.

Step 1: Go to the Data Migration page

Use either the DTS console or the DMS console.

DTS console

1. Log on to the DTS console.

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

3. In the upper-left corner, select the region where the migration instance resides.

DMS console

Steps may vary based on the DMS console mode and layout. See Simple mode and Customize the layout and style of the DMS console.

1. Log on to the DMS console.

2. In the top navigation bar, move your pointer over Data + AI > DTS (DTS) > Data Migration.

3. From the drop-down list to the right of Data Migration Tasks, select the region where the instance resides.

Step 2: Configure source and destination databases

1. Click Create Task.

2. Read the Limits displayed at the top of the page before proceeding.

3. Configure the source and destination databases using the following parameters.

Source database

Destination database

1. Click Test Connectivity and Proceed.

   DTS server IP address ranges must be added to the security settings of both databases. DTS can add these automatically, or you can add them manually. See Add the IP address ranges of DTS servers.

Step 3: Configure migration objects

On the Configure Objects page, set the following parameters.

Parameter	Description
Migration Types	Select the migration types to run. To minimize service interruption, select Schema Migration, Full Data Migration, and Incremental Data Migration. To run full migration only, select Schema Migration and Full Data Migration. Note If you skip Schema Migration, create the target database and tables manually and enable the object name mapping feature in Selected Objects before starting the task.
DDL and DML Operations to Be Synchronized	Select the SQL operations for incremental migration at the instance level. See SQL operations supported for incremental migration. To configure at the database or table level, right-click the object in Selected Objects and select the operations in the dialog box.
Merge Tables	Select Yes to merge all selected source tables into a single destination table. DTS adds a __dts_data_source column to store the data source. To merge only specific tables, create two separate migration tasks. Select No (default) to migrate tables without merging. Warning Do not perform DDL operations that change source database or table schemas during migration. Doing so may cause data inconsistency or task failure.
Processing Mode of Conflicting Tables	Precheck and Report Errors (default): checks whether destination tables have the same names as source tables. If identical names exist, the precheck fails and the task cannot start. Use the object name mapping feature to rename conflicting tables. Ignore Errors and Proceed: skips the name conflict check. If source and destination have the same schema and a record shares a primary key with an existing destination record — during full migration, DTS skips the record; during incremental migration, DTS overwrites it. If schemas differ, only matching columns are migrated or the task fails. Use with caution.
Capitalization of Object Names in Destination Instance	Controls the capitalization of database, table, and column names in the destination. Default: DTS default policy. See Specify the capitalization of object names in the destination instance.
Source Objects	Select columns, tables, or databases to migrate, then click to add them to Selected Objects. Note If you select a table, associated views, triggers, and stored procedures are not migrated. If you select a database: tables with a primary key use it as the distribution key; tables without a primary key get an auto-increment primary key, which may cause data inconsistency.
Selected Objects	To rename a single object, right-click it and follow the instructions in Rename objects one by one. To rename multiple objects at once, click Edit in the upper-right corner. See Rename objects in batches. Note Renaming an object may break migration for objects that depend on it. To filter rows, right-click the table and set a WHERE condition. See Configure filter conditions.

Step 4: Configure advanced settings

Click Next: Advanced Settings and configure the following parameters.

Step 5: Configure database and table fields (optional)

Click Next: Configure Database and Table Fields to set the Type, Primary Key Column, Distribution Key, Partition Key, Partitioning Rules, and Partition Lifecycle for tables in the destination database.

This step is available only when Schema Migration is selected. Set Definition Status to All to view all tables. You can select multiple columns as a composite Primary Key Column, then choose one or more of those columns as the Distribution Key and Partition Key. See CREATE TABLE.

Step 6: Run the precheck

Click Next: Save Task Settings and Precheck.

Tip: Before saving, click Preview OpenAPI parameters to view the parameters that the corresponding API operation uses when configuring this task.

DTS runs a precheck before the task starts. If any item fails:

1. Click View Details next to the failed item.

2. Fix the underlying issue based on the check results.

3. Click Precheck Again.

If an item generates an alert:

• If the alert cannot be ignored, click View Details next to the failed item and troubleshoot the issues. Then click Precheck Again.

• If you want to ignore the alert, follow these steps:

  1. Click Confirm Alert Details.

  2. In the dialog box, click Ignore, then click OK.

  3. Click Precheck Again.

Step 7: Purchase an instance and start the task

1. Wait until Success Rate reaches 100%, then click Next: Purchase Instance.

2. On the Purchase Instance page, configure the following parameters.

   Parameter	Description
   Resource Group	The resource group for the migration instance. Default: default resource group. See What is Resource Management?
   Instance Class	The instance class determines migration speed. Select a class based on your requirements. See Instance classes of data migration instances.

3. Read and accept Data Transmission Service (Pay-as-you-go) Service Terms by selecting the check box.

4. Click Buy and Start, then click OK in the confirmation dialog.

Track progress on the Data Migration page.

• Schema migration and full data migration tasks stop automatically when complete. The Status column shows Completed.

• Incremental data migration tasks run continuously and do not stop automatically. The Status column shows Running. Stop the task manually before switching your workload to the destination.