What's New in Semantic Technologies?

For Oracle Database release 11.1, the focus of this manual expands to include Oracle Database semantic technologies, which include Resource Description Framework (RDF), which was supported in Release 10.2, and a subset of the Web Ontology Language (OWL), support for which is new in the current release.

In addition to expanded capabilities, some naming conventions associated with the API may changes. For example, names that include "SDO_RDF" may be changed for data types, function names, and PL/SQL package names. However, all applications created in the previous release using supported names for that release will continue to run.

Note:

These changes are only partially reflected in the content of this draft; however, the organization and the content of this draft will be periodically updated to reflect the new capabilities and names

Storage Model Enhancements and Migration

The storage model has been enhanced to support OWL inferencing: some internal data structures and indexes have been changed, added, and removed. These changes also result in enhanced performance.

Because of the extent of these changes, if you have semantic data that you used with the previous release, you must upgrade that data to migrate it to the new format before you can use any new features for this release. Semantic data is upgraded as part of the required procedure described in Section 1.10.

Support for OWL Inferencing

Support has been added to support storing, validating, and querying Web Ontology Language (OWL)-based ontologies. Support is provided for a subset of the OWL DL language.

To query ontology data, you can use table functions and operators that examine semantic relationships, such as SEM_MATCH, SEM_RELATED, and SEM_DISTANCE.

New Bulk Loading Interface for Improved Performance

You can improve performance for bulk loading of semantic data in bulk using a staging table and calling the SEM_APIS.BULK_LOAD_FROM_STAGING_TABLE procedure. For more information, see Section 1.7.1.

Ontology-Assisted Querying of Relational Data

You can go beyond syntactic matching to perform semantic relatedness-based querying of relational data, by associating an ontology with the data and using the new SEM_RELATED operator (and optionally its SEM_DISTANCE ancillary operator). The new SEM_INDEXTYPE index type improves performance for semantic queries.

Required Procedure for Using Semantic Technology Support

Before you can use any types, synonyms, or PL/SQL packages related to Oracle semantic technologies support, you must run the $ORACLE_HOME/md/admin/catsem10i.sql or $ORACLE_HOME/md/admin/catsem11i.sql script, as explained in Section 1.10. This procedure installs Release 11.1 support for semantic technologies support, and it migrates any existing Release 10.2 RDF data to the Release 11.1 format.