Migrate data from a self-managed Oracle database to an AnalyticDB for PostgreSQL instance

Billing

Precautions

• During full data migration, DTS uses read and write resources of the source and destination databases. This may increase the loads of the database servers. Before you migrate data, evaluate the impact of data migration on the performance of the source and destination databases. We recommend that you migrate data during off-peak hours.
• If a data migration task fails, DTS automatically resumes the task. Before you switch your workloads to the destination database, stop or release the data migration task. Otherwise, the data in the source database will overwrite the data in the destination database after the task is resumed.
• If the self-managed Oracle database is deployed in a Real Application Cluster (RAC) architecture and is connected to DTS over an Alibaba Cloud virtual private cloud (VPC), you must connect the Single Client Access Name (SCAN) IP address of the Oracle RAC and the virtual IP address (VIP) of each node to the VPC and configure routes. The settings ensure that your DTS task can run as expected. For more information, see Configure a route between DTS and Express Connect, VPN Gateway, or Smart Access Gateway.
  Notice When you configure the source Oracle database in the DTS console, you can specify the SCAN IP address of the Oracle RAC as the database endpoint or IP address.

Migration types

Permissions required for database accounts

For more information about how to create and authorize a database account, see the following topics:

• Self-managed Oracle database: CREATE USER and GRANT
• AnalyticDB for PostgreSQL: Configure an account

Enable logging and grant fine-grained permissions to an Oracle database account

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;
   Force logging	Execute the following statements to enable force logging: alter database force logging;

2. Grant fine-grained permissions to an Oracle database account
   Oracle Versions 9i to 11g Oracle Versions 12c to 19c (Multitenant Architecture) Oracle Versions 12c to 19c (Non-Multitenant Architecture)

   # 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;
   grant select on v$database to rdsdt_dtsacct;
   grant select on dba_objects to rdsdt_dtsacct;
   grant select on DBA_TAB_COMMENTS to rdsdt_dtsacct;
   grant select on dba_tab_cols to rdsdt_dtsacct;

   # Switch to the pluggable database (PDB). Create a database account, for example, rdsdt_dtsacct, and grant permissions to the account.
   ALTER SESSION SET container = ORCLPDB1;
   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  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;
   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;
   -- V$PDBS privileges
   grant select on V_$PDBS to rdsdt_dtsacct;
   grant select on v$database to rdsdt_dtsacct;
   grant select on dba_objects to rdsdt_dtsacct;
   grant select on DBA_TAB_COMMENTS to rdsdt_dtsacct;
   grant select on dba_tab_cols to rdsdt_dtsacct;
   
   # Switch to the CDB$ROOT, which is the root container of the container database (CDB). Create a database account and grant permissions to the account by using one of the following methods:
   ALTER SESSION SET container = CDB$ROOT;
   Method 1: Create a global account starting with C##, for example, C##rdsdt_dtsacct, and grant permissions to the account. If you use this method, you must submit a ticket and contact the DTS team to modify some parameters. The link to submit a ticket is provided in the note.
   create user C##rdsdt_dtsacct IDENTIFIED BY rdsdt_dtsacct;
   grant create session to C##rdsdt_dtsacct;
   grant connect to C##rdsdt_dtsacct;
   grant resource to C##rdsdt_dtsacct;
   grant select on v_$logmnr_contents to C##rdsdt_dtsacct;
   grant LOGMINING to C##rdsdt_dtsacct;
   grant EXECUTE_CATALOG_ROLE to C##rdsdt_dtsacct;
   grant execute on sys.dbms_logmnr to C##rdsdt_dtsacct;
   grant select on v$database to rdsdt_dtsacct;
   grant select on dba_objects to rdsdt_dtsacct;
   grant select on DBA_TAB_COMMENTS to rdsdt_dtsacct;
   grant select on dba_tab_cols to rdsdt_dtsacct;
   Method 2: Create a database account, for example, rdsdt_dtsacct, and grant permissions to the account. If you use this method, you must modify the default parameters of the Oracle database.
   alter session set "_ORACLE_SCRIPT"=true;
   create user rdsdt_dtsacct IDENTIFIED BY rdsdt_dtsacct;
   grant create session to rdsdt_dtsacct;
   grant connect to rdsdt_dtsacct;
   grant select on v_$logmnr_contents to rdsdt_dtsacct;
   grant LOGMINING TO rdsdt_dtsacct;
   grant EXECUTE_CATALOG_ROLE to rdsdt_dtsacct;
   grant execute on sys.dbms_logmnr to rdsdt_dtsacct;
   grant select on v$database to rdsdt_dtsacct;
   grant select on dba_objects to rdsdt_dtsacct;
   grant select on DBA_TAB_COMMENTS to rdsdt_dtsacct;
   grant select on dba_tab_cols to rdsdt_dtsacct;

   # 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 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_$logmnr_contents to rdsdt_dtsacct;
   grant select on sys.USER$ 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;
   grant LOGMINING TO rdsdt_dtsacct;
   grant EXECUTE_CATALOG_ROLE to rdsdt_dtsacct;
   grant execute on sys.dbms_logmnr to rdsdt_dtsacct;
   grant select on v$database to rdsdt_dtsacct;
   grant select on dba_objects to rdsdt_dtsacct;
   grant select on DBA_TAB_COMMENTS to rdsdt_dtsacct;
   grant select on dba_tab_cols to rdsdt_dtsacct;

   Note To create a global account starting with C## for a multitenant CDB$ROOT in Oracle 12c to 19c, you must Submit a ticket and contact the DTS team to modify some parameters.

Procedure

1. Log on to the DTS console.
2. In the left-side navigation pane, click Data Migration.
3. At the top of the Migration Tasks page, select the region where the destination instance resides.
4. In the upper-right corner of the page, click Create Migration Task.
5. Configure the source and destination databases.
   

   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	Instance Type	Select an instance type based on the deployment of the source database. In this example, select User-Created Database in ECS Instance. Note If you select other instance types, you must prepare the environment that is required for the source database. For more information, see Preparation overview.
   	Instance Region	Select the region of the Elastic Compute Service (ECS) instance on which the self-managed Oracle database is hosted.
   	ECS Instance ID	Select the ID of the ECS instance on which the self-managed Oracle database is hosted.
   	Database Type	Select Oracle.
   	Port Number	Enter the service port number of the self-managed Oracle database. The default port number is 1521.
   	Instance Type	If you select Non-RAC Instance, you must specify the SID parameter. RAC Instance: If you select this option, you must specify the Service Name. In this example, select Non-RAC Instance.
   	SID	Enter the system ID (SID) of the self-managed Oracle database.
   	Database Account	Enter the account of the self-managed Oracle database. For more information about the permissions that are required for the account, see Permissions required for database accounts.
   	Database Password	Enter the password of the database account. Note After you specify the information about the self-managed Oracle database, you can click Test Connectivity next to Database Password to check whether the information is valid. If the information is valid, the Passed message appears. If the Failed message appears, click Check next to Failed. Then, modify the information based on the check results.
   Destination Database	Instance Type	Select AnalyticDB for PostgreSQL.
   	Instance Region	Select the region where the destination AnalyticDB for PostgreSQL instance resides.
   	Instance ID	Select the ID of the AnalyticDB for PostgreSQL instance.
   	Database Name	Enter the name of the destination database.
   	Database Account	Enter the database account of the destination AnalyticDB for PostgreSQL instance. For more information about the permissions that are required for the account, see Permissions required for database accounts.
   	Database Password	Enter the password of the database account.

6. In the lower-right corner of the page, click Set Whitelist and Next.
   DTS adds the CIDR blocks of DTS servers to the inbound rule of the ECS instance and the whitelist of the AnalyticDB for PostgreSQL instance. This ensures that DTS servers can connect to the source and destination instances.
7. Select the migration types, the operation types, and the objects to be migrated.
   

   Setting	Description
   Select the migration types	To perform only full data migration, select Schema Migration and Full Data Migration. To ensure service continuity during data migration, select Schema Migration, Full Data Migration, and Incremental Data Migration. Note If Incremental Data Migration is not selected, do not write data to the source database during full data migration. This ensures data consistency between the source and destination databases.
   Select the operation types	Select the types of operations that you want to synchronize during incremental data migration. All operation types are selected by default.
   Select the objects to be migrated	Select one or more objects from the Available section and click the icon to move the objects to the Selected section. Note You can select columns, tables, or schemas as the objects to be migrated. By default, after an object is migrated to the destination database, the name of the object remains unchanged. You can use the object name mapping feature to rename the objects that are migrated to the destination database. For more information, see Object name mapping. 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.
   Specify whether to rename objects	You can use the object name mapping feature to rename the objects that are migrated to the destination instance. For more information, see Object name mapping.
   Specify the retry time for failed connections to the source or destination database	By default, if DTS fails to connect to the source or destination database, DTS retries within the next 12 hours. You can specify the retry time based on your needs. If DTS reconnects to the source and destination databases within the specified time, DTS resumes the data migration task. Otherwise, the data migration task fails. Note When DTS retries a connection, you are charged for the DTS instance. We recommend that you 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.
   Enclose object names in quotation marks	Specify whether you need to enclose object names in quotation marks. If you select Yes and the following conditions are met, DTS encloses object names in single or double quotation marks during schema migration and incremental data migration. The business environment of the source database is case-sensitive but the database name contains both uppercase and lowercase letters. A source table name does not start with a letter and contains characters other than letters, digits, and special characters. Note A source table name can contain only the following special characters: underscores (_), number signs (#), and dollar signs ($). The names of the schemas, tables, or columns that you want to migrate are keywords, reserved keywords, or invalid characters in the destination database.

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

   Note

   • For more information about primary key columns and distribution keys, see Define constraints and Define table distribution.
   • If DTS identifies tables without primary keys, the option Set Primary Keys and Distribution Keys of All Tables Without Primary Keys to ROWID is displayed on the preceding page. If you select this option, DTS adds the ROWID field as the primary key and distribution key to the destination tables.
9. In the lower-right corner of the page, click Precheck.
   Note

   • Before you can start the data migration task, a precheck is performed. You can start the data migration 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.
10. After the task passes the precheck, click Next.
11. In the Confirm Settings dialog box, specify the Channel Specification parameter and select Data Transmission Service (Pay-As-You-Go) Service Terms.
12. Click Buy and Start to start the data migration task.
    • Schema migration and full data migration

      We recommend that you do not manually stop the task during full data migration. Otherwise, the data migrated to the destination database will be incomplete. You can wait until the data migration task automatically stops.

    • Schema migration, full data migration, and incremental data migration

      The task does not automatically stop during incremental data migration. You must manually stop the task.

      Notice We recommend that you select an appropriate time to manually stop the data migration task. For example, you can stop the task during off-peak hours or before you switch your workloads to the destination cluster.
      1. Wait until Incremental Data Migration and The migration task is not delayed appear in the progress bar of the migration task. Then, stop writing data to the source database for a few minutes. The delay time of incremental data migration may be displayed in the progress bar.
      2. Wait until the status of incremental data migration changes to The migration task is not delayed again. Then, manually stop the migration task.