1.24 Required Migration of Pre-12.2 RDF Data

If you have any RDF data created using Oracle Database 11.1. 11.2, or 12.1, then before you use it in an Oracle Database 12.2 environment, you must migrate this data.

To perform the migration, use the SEM_APIS.MIGRATE_DATA_TO_CURRENT procedure. This applies not only to your existing RDF data, but also to any other RDF data introduced into your environment if that data was created using Oracle Database 11.1. 11.2, or 12.1

The reason for this requirement is for optimal performance of queries that use ORDER BY. Effective with Release 12.2, Oracle Database creates, populates, and uses the ORDER_TYPE, ORDER_NUM, and ORDER_DATE columns (new in Release 12.2) in the RDF_VALUE$ table (described in Statements). The SEM_APIS.MIGRATE_DATA_TO_CURRENT procedure populates these order-related columns. If you do not do this, those columns will be null for existing data.

You run this procedure after upgrading to Oracle Database Release 12.2. If you later bring into your Release 12.2 environment any RDF data that was created using an earlier release, you must also run the procedure before using that data. Running the procedure can take a long time with large amounts of RDF data, so consider that in deciding when to tun it. (Note that using the INS_AS_SEL=T option improves the performance of the SEM_APIS.MIGRATE_DATA_TO_CURRENT procedure with large data sets.)