From PostgreSQL wiki
GridSQL is an open source shared-nothing clustered database system for data warehousing designed for PostgreSQL. GridSQL includes intelligence to parallelize over multiple servers for achieving faster query response times.
Not actively developed and maintained any more, replaced by Stado (http://sourceforge.net/projects/gridsql/forums/forum/787558/topic/4514520).
- Project website: http://sourceforge.net/projects/gridsql/
- Source code: http://gridsql.cvs.sourceforge.net/viewvc/gridsql/