When it comes to enterprise databases, the name Oracle (ORCL) is usually the first one that comes to mind. This is why it was inevitable that the company's proposed $7.4 billion purchase of Sun Microsystems (JAVA) would encounter headwinds from the antitrust authorities, especially the European Union due to the fact that Sun owns the open-source database system, MySQL.

While Oracle can often use lots of bluster, the company is also a realist. And, it certainly wants to close its deal for Sun, which has been languishing because of the uncertainty.

Open source software continues its torrid pace. In fact, according to a report from the 451 Group, the sector saw its biggest quarter for venture funding -- hitting $203.75 million, which is up from $100.4 million in the same period a year ago.

Why the interest? Well, I had a chance to interview Matthew Aslett, who is an analyst of enterprise software at the 451 Group:

Your take on the focus on open source?

VCs are interested in open source vendors because the open source development and distribution models reduce start-up costs and lower the barriers to entry. Some VCs have also cited increased code quality as a reason for investing in open source as the model enables a broader range of product testing and rapid innovation. There are a number of VCs that are sold on the open source model, and some have even stated that they would only consider investing in a software vendor if it was using and producing open source. Open source vendor revenues are lower than more established traditional rivals today, but most vendors are still in their infancy. Recent mergers and acquisitions involving open source vendors such as Zimbra, JBoss and MySQL have proved that the returns are there and are likely to encourage more VCs to look favorably on open source.

Last year, there was quite a bit of consolidation in the software sector, such as from Oracle (NASDAQ: ORCL), Microsoft (NASDAQ: MSFT) and even SAP (NYSE: SAP).

And, yes the dealmaking is continuing into 2008. For example, this week, Sun Microsystems (NASDAQ: JAVA) announced it is shelling out $1 billion for MySQL, which develops an open source database.

Well, I had a chance to interview Raven Zachary, who is the Research Director of Open Source at the 451 Group:

Why the interest in open source? What is the business model -- in light of the "free" part?

The interest in open source has been driven by end-user demand. As more open source (from operating systems to web servers to middleware to data integration to databases and beyond) is used by end-user organizations, there is an opportunity for monetization around open source. Back in 2004, we saw the beginning of a new wave on open source venture funding that has continued, peaking in 2006, but still at $300m+ per year. As this new wave of commercial open source companies build out a customer base, they become attractive targets for larger IT vendors.

Sun Microsystems, Inc. (NASDAQ: JAVA) will be buying open-source database software company MySQL AB for about $1 billion, both companies announced this morning. MySQL, based in Sweden, makes a very popular database application used by global nameplates we all recognize such as Google (NASDAQ: GOOG), Nokia Corp. (NYSE: NOK) and Facebook, Inc.

The deal includes an $800 million cash payment by Sun and $200 million in options to arrive at the billion-dollar total. MySQL CEO Marten Mickos said "Sun's culture and business model complements MySQL's own by sharing the same ideals that we have had since our foundation -- software freedom, online innovation and community and partner participation."

Sun's movement into the open-source software universe recently has signaled a huge shift in its strategy under current CEO Jonathan Schwartz.