gplink is a program I wrote that makes it possible to create an External Table in Greenplum that connects to ANY JDBC connection through a gpfdist process.
When to Use
Use this for either loading data into Greenplum from a JDBC source. This is similar to Outsourcer but that tool automates far more tasks and only works for SQL Server or Oracle.
You can also create federated queries between Greenplum and a JDBC source. Please use caution when doing this as the External Table does not do predicate push down so the entire query must complete in the source database before any filters can be applied.
Documentation and Source Code
gplink Github Repository
Download Version 1.0.1