Ora2Pg is a free tool used to migrate an Oracle database to a PostgreSQL compatible schema. It connects your
Oracle database, scan it automaticaly and extracts its structure or data, it then generates SQL scripts that you can
load into your PostgreSQL database.
Ora2Pg can be used from reverse engineering Oracle database to huge enterprise database migration or simply to replicate
some Oracle data into a PostgreSQL database. It is really easy to used and doesn't need any Oracle database knowledge than
providing the parameters needed to connect to the Oracle database.
The Eclipse Persistence Services Project (EclipseLink) project's goal is to provide a complete persistence framework that is both comprehensive and universal. It will run in any Java environment and read and write objects to virtually any type of data source, including relational databases, XML, or EIS systems. EclipseLink will focus on providing leading edge support, including advanced feature extensions, for the dominant persistence standards for each target data source; Java Persistence API (JPA) for relational databases, Java Architecture for XML Binding (JAXB) for XML, J2EE Connector Architecture (JCA) for EIS and other types of legacy systems, and Service Data Objects (SDO).
SymmetricDS is web-enabled, database independent, data synchronization/replication software. It uses web and database technologies to replicate tables between relational databases in near real time. The software was designed to scale for a large number of databases, work across low-bandwidth connections, and withstand periods of network outage.