Data Transmission Service:Track data changes from a self-managed Oracle database

Prerequisites

• The version of the self-managed Oracle database is 9i, 10g, or 11g. Real Application Cluster (RAC) or pluggable database (PDB) instances are not supported.
• Supplemental logging is enabled for the self-managed Oracle database. The SUPPLEMENTAL_LOG_DATA_PK and SUPPLEMENTAL_LOG_DATA_UI parameters are set to Yes. For more information, see Supplemental Logging.
• The self-managed Oracle database is running in ARCHIVELOG mode. Archived log files are accessible and a suitable retention period is set for archived log files. For more information, see Managing Archived Redo Log Files.
• An ApsaraDB RDS for MySQL instance is created. For more information, see Create an ApsaraDB RDS for MySQL instance.

Limits

Before you begin

Log on to the source Oracle database, create a database account, and grant the database administrator (DBA) permissions to the account. For more information, see CREATE USER and GRANT.

1. Enable archive logging and supplemental logging.

   Type	Procedure
   Archive logging	Execute the following statements to enable archive logging: shutdown immediate; startup mount; alter database archivelog; alter database open; archive log list;
   Supplemental logging	Enable supplemental logging at the database or table level: Note You can enable database-level supplemental logging to ensure the stability of DTS tasks. You can enable table-level supplemental logging to reduce the disk usage of the source Oracle database. Enable database-level supplemental logging Enable minimal supplemental logging: alter database add supplemental log data; Enable primary key and unique key supplemental logging at the database level: alter database add supplemental log data (primary key,unique index) columns; Enable table-level supplemental logging Enable minimal supplemental logging: alter database add supplemental log data; Enable table-level supplemental logging by using one of the following methods: Enable primary key supplemental logging at the table level: alter table table_name add supplemental log data (primary key) columns; Enable table-level supplemental logging for all columns: alter table tb_name add supplemental log data (all) columns ;

2. Grant fine-grained permissions to an Oracle database account
   Oracle Versions 9i to 11g

   # Create a database account, for example, rdsdt_dtsacct, and grant permissions to the account.
   create user rdsdt_dtsacct IDENTIFIED BY rdsdt_dtsacct;
   grant create session to rdsdt_dtsacct;
   grant connect to rdsdt_dtsacct;
   grant resource to rdsdt_dtsacct;
   grant execute on sys.dbms_logmnr to rdsdt_dtsacct;
   grant select on V_$LOGMNR_LOGS to rdsdt_dtsacct;
   grant select on all_objects to rdsdt_dtsacct;
   grant select on all_tab_cols to rdsdt_dtsacct;
   grant select on dba_registry to rdsdt_dtsacct;
   grant select any table to rdsdt_dtsacct;
   grant select any transaction to rdsdt_dtsacct;
   -- v$log privileges
   grant select on v_$log to rdsdt_dtsacct;
   -- v$logfile privileges
   grant select on v_$logfile to rdsdt_dtsacct;
   -- v$archived_log privileges
   grant select on v_$archived_log to rdsdt_dtsacct;
   -- v$parameter privileges
   grant select on v_$parameter to rdsdt_dtsacct;
   -- v$database privileges
   grant select on v_$database to rdsdt_dtsacct;
   -- v$active_instances privileges
   grant select on v_$active_instances to rdsdt_dtsacct;
   -- v$instance privileges
   grant select on v_$instance to rdsdt_dtsacct;
   -- v$logmnr_contents privileges
   grant select on v_$logmnr_contents to rdsdt_dtsacct;
   -- system tables
   grant select on sys.USER$ to rdsdt_dtsacct;
   grant select on SYS.OBJ$ to rdsdt_dtsacct;
   grant select on SYS.COL$ to rdsdt_dtsacct;
   grant select on SYS.IND$ to rdsdt_dtsacct;
   grant select on SYS.ICOL$ to rdsdt_dtsacct;
   grant select on SYS.CDEF$ to rdsdt_dtsacct;
   grant select on SYS.CCOL$ to rdsdt_dtsacct;
   grant select on SYS.TABPART$ to rdsdt_dtsacct;
   grant select on SYS.TABSUBPART$ to rdsdt_dtsacct;
   grant select on SYS.TABCOMPART$ to rdsdt_dtsacct;

Procedure

1. Go to the Change Tracking 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) > Change Tracking.
2. To the right side of Change Tracking Tasks, select the region in which you want to create the change tracking task.
3. Click Create Task. On the page that appears, configure the source database and the consumer network type.
   Warning After you select the source instance, we recommend that you read the limits displayed at the top of the page. This helps you create and run the change tracking task.

   Section	Parameter	Description
   N/A	Task Name	DTS automatically generates a task name. We recommend that you specify an informative name to identify the task. You do not need to use a unique task name.
   Source Database	Select Template	The instance to which the source database belongs. You can choose whether to use an existing instance based on your business requirements. If you use an existing instance, DTS automatically applies the parameter settings of the source database. If you do not use an existing instance, you must set parameters for the source database.
   	Database Type	Select Oracle.
   	Access Method	Select the type of the source instance. In this example, Self-managed Database on ECS is selected. Note If your source database is a self-managed database, you must deploy the network environment for the database. For more information, see Preparation overview.
   	Instance Region	Select the region where the self-managed Oracle database resides.
   	ECS Instance ID	Select the ID of the ECS instance that hosts the self-managed Oracle database.
   	Port Number	Enter the service port number of the self-managed Oracle database. The default port number is 1521.
   	Oracle Type	If you select Non-RAC Instance, you must specify the SID parameter. If you select RAC or PDB Instance, you must specify the Service Name parameter. Notice RAC or PDB instances are not supported. In this example, Non-RAC Instance is selected.
   	Database Account	Enter the account of the self-managed Oracle database. For information about the permissions that are required for the account, see Before you begin.
   	Database Password	Enter the password of the database account.
   Consumer Network Type	Classic VPC	Select the network type of the change tracking instance. Note If your change tracking client is deployed on a local server, you can select Classic or VPC. If your change tracking client is deployed on an ECS instance, we recommend that you select the network of the ECS instance. For example, if the ECS instance is deployed in a VPC, select VPC as the network type and specify the VPC and vSwitch parameters. If you track data changes over internal networks, the network latency is minimal. Classic If you select Classic, no other configurations are required. For more information, see Classic network. VPC If you select VPC, you must specify the VPC and vSwitch parameters. For more information, see VPCs. Notice After a change tracking task is configured, you cannot change the network type. Data changes are tracked and consumed over the specified type of network.

4. In the lower part of the page, click Test Connectivity and Proceed.
5. Select objects for the task and configure advanced settings.
   • Basic Settings

     Parameter	Description
     Data Change Types	Data Update DTS tracks data updates of the selected objects, including the INSERT, DELETE, and UPDATE operations. Schema Update DTS tracks the create, delete, and modify operations that are performed on all object schemas of the source instance. You must use the change tracking client to filter the required data.
     Source Objects	Select one or more objects from the Source Objects section and click the icon to move the objects to the Selected Objects section. Note You can select tables or databases as the objects for change tracking. If you select a database as the object, DTS tracks data changes of all objects, including new objects in the database. If you select a table as the object, DTS tracks only data changes of this table. In this case, if you want to track data changes of another table, you must add the table to the selected objects. For more information, see Modify the objects for change tracking.

   • Advanced Settings

     Parameter	Description
     Set Alerts	Specify whether to configure alerting for the change tracking task. If the task fails or the latency exceeds the specified threshold, the specified alert contacts can receive notifications. Valid values: No: does not configure alerting. Yes: configures alerting. In this case, you must also specify the alert threshold and alert contacts.
     Retry Time for Failed Connection	The retry time range for failed connections. If the change tracking task fails, DTS immediately retries a connection within the time range. Valid values: 10 to 1440. Unit: minutes. Default value: 120. We recommend that you set the time range to more than 30 minutes. If DTS reconnects to the source instance within the specified time range, DTS resumes the change tracking task. Otherwise, the change tracking task fails. Note If an instance serves as the source database of multiple change tracking tasks, the shortest retry time range that is set for the instance takes precedence. When DTS retries a connection, you are charged for the DTS instance. We recommend that you specify the retry time range based on your business requirements. You can also release the DTS instance at your earliest opportunity after the source and destination instances are released.
     Configure ETL	Specify whether to configure the extract, transform, and load (ETL) feature. For more information, see What is ETL? Valid values: Yes: configures the ETL feature. You can enter your policy in the code editor. No: does not configure the ETL feature.

6. Click Next: Save Task Settings and Precheck in the lower part of the page.
   Note

   • Before you can start the change tracking task, DTS performs a precheck. You can start the change tracking task only after the task passes the precheck.
   • If the task fails to pass the precheck, you can click the icon next to each failed item to view details.
     • You can troubleshoot the issues based on the causes and run a precheck again.
     • If you do not need to troubleshoot the issues, you can ignore failed items and run a precheck again.
7. Wait until the Success Rate becomes 100%. Then, click Next: Purchase Instance.
8. On the Purchase Instance page, specify the billing method of the change tracking instance. The following table describes the parameters.

   Parameter	Description
   Billing Method	Subscription: You can pay for your subscription when you create an instance. We recommend that you select the subscription billing method for long-term use because it is more cost-effective than the pay-as-you-go billing method. You can save more costs with longer subscription periods. Pay-as-you-go: A pay-as-you-go instance is billed on an hourly basis. We recommend that you select the pay-as-you-go billing method for short-term use. If you no longer require your pay-as-you-go instance, you can release it to reduce costs.
   Billing Type of Change Tracking Instance	If you select the subscription billing method, you can select only USD 120 per month for configuration fee (no data traffic fee) as the billing type of the change tracking instance.
   Subscription Length	If you select the subscription billing method, set the subscription length and the number of instances that you want to create. The subscription length can be one to nine months or one to three years. Note This parameter is available only if you select the subscription billing method.

   Note When a client accesses the change tracking instance over the Internet, DTS charges Internet traffic fee.
9. Read and select Data Transmission Service (Pay-as-you-go) Service Terms.
10. Click Buy and Start to start the change tracking task. You can view the progress of the task in the task list.