This topic describes how to migrate data from a self-managed Oracle database to a PolarDB for MySQL cluster by using Data Transmission Service (DTS). DTS supports schema migration, full data migration, and incremental data migration. When you migrate data from a self-managed Oracle database, you can select all of the supported migration types to ensure service continuity.
Prerequisites
- The source Oracle database and the destination PolarDB for MySQL cluster are created.
Note
- For more information about how to create the destination PolarDB for MySQL cluster, see Purchase a pay-as-you-go cluster and Purchase a subscription cluster.
- For more information about the supported versions of the source database and the destination cluster, see Overview of data migration scenarios.
- 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.
- Supplemental logging, including SUPPLEMENTAL_LOG_DATA_PK and SUPPLEMENTAL_LOG_DATA_UI, is enabled for the self-managed Oracle database. For more information, see Supplemental Logging.
- The destination PolarDB for MySQL cluster is created. For more information, see Purchase a pay-as-you-go cluster and Purchase a subscription cluster.
- The available storage space of the destination PolarDB for MySQL cluster is larger than the total size of the data in the self-managed Oracle database.
Limits
Category | Description |
---|---|
Limits on the source database |
|
Other limits |
|
Special cases | If the destination database runs on a PolarDB for MySQL cluster, take note of the
following limits:
|
Billing
Migration type | Task configuration fee | Internet traffic fee |
---|---|---|
Schema migration and full data migration | Free of charge. | Charged only when data is migrated from Alibaba Cloud over the Internet. For more information, see Billing overview. |
Incremental data migration | Charged. For more information, see Billing overview. |
Migration types
Migration type | Description |
---|---|
Schema migration | DTS migrates the schemas of the required objects to the destination database.
DTS has the following limits on schema migration for tables and indexes:
Note
Warning Oracle and MySQL are heterogeneous databases. DTS does not ensure that the schemas
of the source and destination databases are consistent after schema migration. We
recommend that you evaluate the impact of data type conversion on your business. For
more information, see Data type mappings between heterogeneous databases.
|
Full data migration | DTS migrates historical data of the required objects from the self-managed Oracle database to the destination database. |
Incremental data migration | DTS retrieves redo log files from the self-managed Oracle database. Then, DTS migrates
incremental data from the self-managed Oracle database to the destination database
in real time.
Incremental data migration allows you to ensure service continuity when you migrate data from a self-managed database. |
SQL operations that can be migrated
Operation type | SQL statements |
---|---|
DML | INSERT, UPDATE, and DELETE |
DDL |
|
Data type mappings
For more information, see Data type mappings between heterogeneous databases.
Preparations
Log on to the source Oracle database, create an account for data collection, and grant permissions to the account.
Database | Schema migration | Full data migration | Incremental data migration |
---|---|---|---|
Self-managed Oracle database | Permissions of the schema owner | Permissions of the schema owner | Database administrator (DBA) |
PolarDB for MySQL cluster | Write permissions on the destination database |
For more information about how to create and authorize a database account, see the following topics:
-
Self-managed Oracle database: CREATE USER and GRANT
- PolarDB for MySQL cluster: Create a database account