Changes in This Release for This Guide

The following changes apply to property graph support that is shipped with Oracle Graph Server and Client.

Oracle Graph Server and Client is required for using the property graph feature of Oracle Database (see Oracle Graph Server and Client Installation), and is released four times a year.

New Features

Significant New Features in Oracle Graph Server and Client 21.2

• Enhanced support for both Supervised and Unsupervised GraphWise Models in PgxML Library:
  • Unsupervised GraphWise, a new algorithm that allows users to generate embeddings for graph vertices without the requirement of labels
  • Edge property support in both Building a Minimal GraphWise Model and Building a Minimal Unsupervised GraphWise Model, that helps users to gain more insight while training a Graphwise model

  See Using the Machine Learning Library (PgxML) for Graphs for more information.

• Python client now supports converting PGQL result set into pandas DataFrame.

  See Converting PGQL result set into pandas dataframe for more information.

• Extended PGQL support for SHORTEST and CHEAPEST path queries on the graph server (PGX). Support added for the following path queries:
  • ALL SHORTEST
  • ANY SHORTEST and ANY CHEAPEST
  • + and {min,max} quantifiers for ANY SHORTEST, ALL SHORTEST and TOP k SHORTEST
• Added support for query cancellation in the Graph Visualization Application.

  See Asynchronous REST Endpoints for more details.

• Added support for Oracle Database Kerberos authentication on the graph server (PGX).

  See Kerberos Enabled Authentication for more information.

• Enhanced support for property graph views:
  • SQLcl support for creating property graph views.
  • Support for querying property graph views using the Graph Visualization Application.
• The Java shell is renamed to opg4j and the Java shell prompt is changed from opg-jshell> to opg4j>.
• The Python shell is renamed to opg4py.
• Added support for executing PGQL queries directly against Oracle Database using the PGQL JDBC driver.

  See Executing PGQL Queries Using JDBC Driver for more information.

• Added a new ID strategy PARTITIONED_IDS that enables graphs to have multiple vertices or edges with the same value as their ID.

  See About Vertex and Edge IDs for more information.

• Added compatibility for Flashback synchronization with PARTITIONED_IDS ID strategy.

  See Keeping the Graph in Oracle Database Synchronized with the Graph Server for more information.

Migrating Property Graph Applications to Oracle Database 21c

From Release 21c onwards, Oracle Graph Server and Client must be installed separately. It is recommended to remove the older property graph libraries from $ORACLE_HOME. See Uninstalling Previous Versions of Property Graph Libraries for more details.

Deprecated Features

• PL/SQL API OPG_APIS.GET_SCN Function
  The PL/SQL API OPG_APIS.GET_SCN function is deprecated. Instead, to retrieve the current SCN (system change number), use the DBMS_FLASHBACK.GET_SYSTEM_CHANGE_NUMBER function:

  SELECT dbms_flashback.get_system_change_number FROM DUAL;

• Two-Table Support

  Support for the two-table format described in Handling Property Graphs Using a Two-Tables Schema was deprecated in 19c and will be removed in a future release.

• Apache Tinkerpop API Support

  Apache Tinkerpop API support for Oracle Database was deprecated in 19c and is scheduled to be removed in a future release.

• OraclePgqlResultSet

  The oracle.pg.rdbms.OraclePgqlResultSet interface was deprecated in 19c and will be removed in a future release. Instead, use the standardized interface oracle.pgql.lang.ResultSet to retrieve values from a PGQL result set.

• Oracle NoSQL Database Support

  Property Graph support for data stored in Oracle NoSQL Database is deprecated and will be removed in a future release.

Desupported Features

• Graph property text search based on Apache Solr/Lucene is desupported. Instead, use Oracle Text or PGQL query expressions.
• The PGX property type DATE is desupported. Instead, use LOCAL_DATE or TIMESTAMP.
• Support for the Apache Groovy-based shell was deprecated in 19c and is now desupported.