Considerations for Choosing a Migration Method….

Various migration methods exist, and each migration method has different benefits, opportunities, requirements, and limitations.

For example, Oracle Cloud Service uses a little-endian platform, so if you are migrating from a big-endian platform, some physical migration approaches are not feasible, or require extra processing to achieve. Also, the use of specific database features, such as materialized views or object data types, may impose restrictions on some migration methods.

Below are the pointers required to be gathered before you start doing the migration,

• On-premises database version
• Database service database version
• On-premises host operating system and version
• On-premises database character set
• Quantity of data, including indexes
• Data types used in the on-premises database
• Storage for data staging
• Acceptable length of system outage
• Network bandwidth

To determine which migration methods might be applicable to your migration scenario, gather the following information.

• Database version of your source database:
  • Oracle Database 11g Release 2 version lower than 11.2.0.3
  • Oracle Database 11g Release 2 version 11.2.0.3 or later
  • Oracle Database 12c Release 1 version lower than 12.1.0.2
  • Oracle Database 12c Release 1 version 12.1.0.2 or later
  • Oracle Database 12c Release 2 version 12.2.0.1
  • Oracle Database 18c
  • Oracle Database 19c
• For Oracle Database 12c Release 1/ Oracle Database 12c Release 2/18c/19c source databases, the architecture of the database:
  • Multitenant container database (CDB)
  • Non-CDB
• Your source database host platform and endian format:
  • Query V$DATABASE to identify the platform name for your source database. Platforms are either little endian or big endian depending on the byte ordering that they use.
  • Query V$TRANSPORTABLE_PLATFORM to view all platforms that support cross-platform tablespace transport, along with the endian format of each platform.
  • The Oracle Cloud Infrastructure Database uses the Linux platform, which is little endian.

The database character set of your source database and the Oracle Cloud Infrastructure Database database:

• By default, databases are configured to use the AL32UTF8 database character set on Oracle Cloud Service. You can select the required character set during provisioning.
• The target database version to which you are migrating on Oracle Cloud Service:
  • Oracle Database 11g Release 2
  • Oracle Database 12c Release 1
  • Oracle Database 12c Release 2
  • Oracle Database 18c
  • Oracle Database 19c