For more than a decade, PostgreSQL has been a cornerstone of the open source database market. In recent years, EnterpriseDB has emerged as a leading vendor supporting and driving PostgreSQL forward.

It will now continue its efforts thanks in part from a little help from IBM (NYSE: IBM). EnterpriseDB is also re-branding and expanding its PostgreSQL efforts to take even more direct aim at its rival MySQL on the open source side and Oracle on the proprietary side.

IBM is joining EnterpriseDB's C round of venture financing which in total raises $10 million for the open source database vendor. Andy Astor, CEO of EnterpriseDB, noted that IBM's was one of four groups participating (including Charles River Ventures, Fidelity Ventures, Valhalla Partners) in this current financing round. To date, EnterpriseDB has raised $37.5 million in venture financing.

Astor told InternetNews.com that IBM called EnterpriseDB and the discussions went from there. Astor added that the discussions with IBM pre-dated the $1 billion acquisition of MySQL by Sun (NASDAQ: JAVA) earlier this year.

Talk of IBM buying out EnterpriseDB was apparently not on the table.

"We are not up for sale," Astor told InternetNews.com. "We always have conversations with various parties but this IBM investment was not about that. They were excited about what we're doing with PostreSQL."

Astor argued that EnterpriseDB has emerged as a leading direct competitor to Oracle's proprietary database and IBM wants a piece. IBM of course has its own proprietary database in DB2, which also competes against both Oracle and PostgreSQL.

In addition to raising more money, EnterpriseDB is also rebranding its two key offerings. EnterpriseDB Postgres will now be called Postgres Plus and EnterpriseDB Advanced server will be called Postgres Plus Advanced Server.

Both products will be based on the recently released PostgreSQL 8.3 database.

Postgres Plus takes the core PostgreSQL database and bundles in additional components to make it easier to install and deploy. Postgres Plus Advanced Server adds in additional closed source Oracle compatibility extensions to PostgreSQL.

Derek Rodner, EnterpriseDB's director of product strategy, explained that Postgres Plus 8.3 also adds in new application quick starts which are supposed to help with installation issues. They will also help in EnterpriseDB's battle against MySQL for open source database supremacy.

"Popular applications like Drupal, MediaWiki and phpBB are all typically just deployed on MySQL," Rodner told InternetNews.com. "But we're hearing that people would like to deploy on PostgreSQL."

In the previous EnterpriseDB PostgreSQL release, a key feature was the MySQL-to-PostgreSQL migration tool. It's a tool that will be in the new version of Postgres Plus in an even more expanded version, helping MySQL users to more easily migrate.

The opportunity for EnterpriseDB in the MySQL migration market is a ripe one. The only other significant vendor to provide commercial support for PostgreSQL is Sun. As part of the Sun's acquisition of MySQL, Sun has announced that MySQL's former CEO Marten Mickos would be heading up Sun's new database group, which also includes PostgreSQL. It's something that doesn't sit well with all PostgreSQL users.

"We've certainly heard a lot of concerns from Postgres people about the Sun acquisition and what that means for Sun's commitment to Postgres," Astor said. "We'll have to wait and see."