Data Transmission Service:Migrate data from Teradata to AnalyticDB for PostgreSQL

Migration types

Prerequisites

Before you begin, make sure that:

• You use the new DTS console. This migration scenario can only be configured in the new DTS console.

• The source Teradata database version is 17 or earlier

• An AnalyticDB for PostgreSQL instance is created. For more information, see Create an instance.

• The available storage of the destination AnalyticDB for PostgreSQL instance is larger than the total data size in the Teradata database

Required permissions

For information about how to create database accounts and grant permissions, see:

• Self-managed Teradata database: Adding Permissions

• AnalyticDB for PostgreSQL instance: Create a database account and Manage users and permissions

Limits

Billing

Create a data migration task

1. Go to the Data Migration Tasks page.

   1. Log on to the Data Management (DMS) console.

   2. In the top navigation bar, click DTS.

   3. In the left-side navigation pane, choose DTS (DTS) > Data Migration.

   - Operations may vary based on the mode and layout of the DMS console. For more information, see Simple mode and Configure the DMS console based on your business requirements. - You can also go to the Data Migration Tasks page of the new DTS console.

2. From the drop-down list next to Data Migration Tasks, select the region in which the data migration instance resides.

   If you use the new DTS console, select the region in the upper-left corner.

3. Click Create Task. Configure the source and destination databases.

   Warning

   After you select the source and destination instances, read the limits at the top of the page to prevent data inconsistency.

   For a self-managed database, you must deploy the network environment. For more information, see Preparation overview.

   Task settings

   Parameter	Description
   Task Name	DTS automatically generates a task name. Specify an informative name to identify the task. A unique task name is not required.

   Source Database

   Parameter	Description
   Database Type	Select Teradata.
   Access Method	Select Public IP Address.
   Instance Region	The region in which the Teradata database resides.
   Hostname or IP address	The endpoint used to access the Teradata database. In this example, a public IP address is used.
   Port Number	The service port number of the Teradata database. Default value: 1025.
   Database Account	The account of the Teradata database. For more information about the permissions required, see Required permissions.
   Database Password	The password of the database account.

   Destination Database

   Parameter	Description
   Database Type	Select AnalyticDB for PostgreSQL.
   Access Method	Select Alibaba Cloud Instance.
   Instance Region	The region in which the destination AnalyticDB for PostgreSQL instance resides.
   Instance ID	The ID of the destination AnalyticDB for PostgreSQL instance.
   Database Name	The name of the destination database in the destination AnalyticDB for PostgreSQL instance.
   Database Account	The database account of the destination AnalyticDB for PostgreSQL instance. For more information about the permissions required, see Required permissions.
   Database Password	The password of the database account.

4. If a whitelist is configured for your self-managed database, add the CIDR blocks of DTS servers to the whitelist. Then, click Test Connectivity and Proceed.

   Warning

   If the CIDR blocks of DTS servers are automatically or manually added to the whitelist of a database or an instance, or to the security group rules of an ECS instance, security risks may arise. Before you use DTS to migrate data, understand and acknowledge the potential risks and take preventive measures, including but not limited to the following measures: enhance the security of your username and password, limit the ports that are exposed, authenticate API calls, regularly check the whitelist or ECS security group rules and forbid unauthorized CIDR blocks, or connect the database to DTS by using Express Connect, VPN Gateway, or Smart Access Gateway.

5. Configure objects to migrate and advanced settings.

   - DTS does not support incremental data migration in this scenario. To maintain data consistency, do not write data to the source database during migration. - You can select columns, tables, or schemas as the objects to be migrated. If you select tables or columns as the objects to be migrated, DTS does not migrate other objects, such as views, triggers, or stored procedures, to the destination database. - If you use the object name mapping feature to rename an object, other objects that are dependent on the object may fail to be migrated. - To filter data with WHERE conditions, right-click an object in the Selected Objects section. In the dialog box that appears, specify the conditions. For more information, see Use SQL conditions to filter data. - If the source and destination databases contain tables with identical names and the tables in the destination database cannot be deleted or renamed, use the object name mapping feature to rename the tables that are migrated to the destination database. For more information, see Map object names.

   Warning

   If you select Ignore Errors and Proceed, data inconsistency may occur, and your business may be exposed to potential risks. - If the source and destination databases have the same schema, DTS does not migrate data records that have the same primary keys as data records in the destination database. - If the source and destination databases have different schemas, only some columns are migrated or the data migration task fails. Proceed with caution.

   - If you set different retry time ranges for multiple data migration tasks that share the same source or destination database, the value that is set later takes precedence. - If DTS retries a connection, you are charged for the operation of the DTS instance. Specify the retry time based on your business needs and release the DTS instance at your earliest opportunity after the source and destination instances are released.

   Basic settings

   Parameter	Description
   Migration Type	Select both Schema Migration and Full Data Migration.
   Processing Mode of Conflicting Tables	Precheck and Report Errors: checks whether the destination database contains tables that have the same names as tables in the source database. If the source and destination databases do not contain identical table names, the precheck is passed. Otherwise, an error is returned during the precheck and the data migration task cannot be started. Ignore Errors and Proceed: skips the precheck for identical table names in the source and destination databases.
   Source Objects	Select one or more objects from the Source Objects section and click the rightward arrow icon to add the objects to the Selected Objects section.
   Selected Objects	To rename an object, right-click the object in the Selected Objects section. For more information, see Map the name of a single object. To rename multiple objects at a time, click Batch Edit in the upper-right corner of the Selected Objects section. For more information, see Map multiple object names at a time.

   Advanced settings

   Parameter	Description
   Set Alerts	Specifies whether to set alerts for the data migration task. If the task fails or the migration latency exceeds the threshold, the alert contacts receive notifications. Valid values: No and Yes. If you select Yes, configure the alert threshold and alert contacts. For more information, see Configure monitoring and alerting when you create a DTS task.
   Retry Time for Failed Connections	The retry time range for failed connections. If the source or destination database fails to be connected after the data migration task is started, DTS immediately retries a connection within the time range. Valid values: 10 to 1440. Unit: minutes. Default value: 720. We recommend that you set the parameter to a value greater than 30.
   Capitalization of Object Names in Destination Instance	The capitalization of database names, table names, and column names in the destination instance. By default, DTS default policy is selected. Select other options to match the default capitalization of object names in the source or destination database. For more information, see Specify the capitalization of object names in the destination instance.

6. Specify the primary key columns and distribution key columns of the tables that you want to migrate to the AnalyticDB for PostgreSQL instance.

   

7. In the lower part of the page, click Next: Save Task Settings and Precheck.

   - Before you can start the data migration task, DTS performs a precheck. You can start the data migration task only after the task passes the precheck. - If the task fails to pass the precheck, click View Details next to each failed item. After you troubleshoot the issues based on the causes, run a precheck again. - If an alert is triggered for an item during the precheck: - If the alert item cannot be ignored, click View Details next to the failed item and troubleshoot the issues. Then, run a precheck again. - If the alert item can be ignored, click Confirm Alert Details. In the View Details dialog box, click Ignore. In the message that appears, click OK. Then, click Precheck Again to run a precheck again. If you ignore the alert item, data inconsistency may occur, and your business may be exposed to potential risks.

8. Wait until the Success Rate value becomes 100%. Then, click Next: Purchase Instance.

9. On the Purchase Instance page, specify the Instance Class for the data migration instance. Different instance classes provide different migration speeds. For more information, see Specifications of data migration instances.

10. Read and select the check box to agree to Data Transmission Service (Pay-as-you-go) Service Terms.

11. Click Buy and Start to start the data migration task. You can view the task progress in the task list.

Result

Monitor migration progress on the Data Migration Tasks page. When the task status changes to Completed, all selected schemas and data have been migrated to the destination AnalyticDB for PostgreSQL instance.

What to do next

After migration completes:

• Verify data completeness by comparing row counts between the source Teradata database and the destination AnalyticDB for PostgreSQL instance.

• Check the precision of FLOAT and DOUBLE columns to make sure they meet your business requirements.

• Stop or release the data migration task before switching workloads to the destination instance. This prevents DTS from resuming the task and overwriting destination data.