Known issues/migration limitations with online migrations from Oracle to Azure DB for PostgreSQL-Single server
Known issues and limitations associated with online migrations from Oracle to Azure Database for PostgreSQL-Single server are described in the following sections.
Oracle versions supported as a source database
Azure Database Migration Service supports connecting to:
- Oracle version 10g, 11g, and 12c.
- Oracle Enterprise, Standard, Express, and Personal Edition.
Azure Database Migration Service doesn't support connecting to multi-tenant container databases (CDBs).
PostgreSQL versions supported as a target database
Azure Database Migration Service supports migrations to Azure Database for PostgreSQL-Single server version 9.5, 9.6, 10 and 11. See the article Supported PostgreSQL database versions for current information on version support in Azure Database for PostgreSQL-Single server.
The following datatypes won't be migrated:
- Nested tables
- User-defined data types
- Virtual columns
- Materialized views based on ROWID column
Also, empty BLOB/CLOB columns are mapped to NULL on the target.
- When Limited-size LOB mode is enabled, empty LOBs on the Oracle source are replicated as NULL values.
- Long object names (over 30 bytes) aren't supported.
- Data in LONG and LONG RAW column can't exceed 64k. Any data beyond 64k will be truncated.
- In Oracle 12 only, any changes to LOB columns aren't supported (migrated).
- UPDATEs to XMLTYPE and LOB columns aren't supported (migrated).
Known issues and limitations
- Customers must use SYSDBA to connect to Oracle.
- Data changes resulting from partition/sub-partition operations (ADD, DROP, EXCHANGE, and TRUNCATE) won't be migrated and may cause the following errors:
- For ADD operations, updates and deletes on the added data may return a "0 rows affected" warning.
- For DROP and TRUNCATE operations, new inserts may result in "duplicates" errors.
- For EXCHANGE operations, both a "0 rows affected" warning and "duplicates" errors may occur.
- Tables whose names contain apostrophes can't be replicated.