For a long time, folks have wondered whether Red Hat will build a software stack; that is, a set of core programs that it makes sense to integrate and sell together in order to provide a single source of infrastructure, billing and -- that most requested part of IT supplier's corporate mass -- a single throat to choke. Red Hat has always revelled in its independence from stack sellers like IBM, Oracle and Microsoft, even after MySQL was sold to Sun and Sun agreed to be sold to Oracle, but with the news that Red Hat has taken a stake in EnterpriseDB, those questions are bound to pop up again.

Of course, Red Hat already has elements such as middleware (through JBoss) and a virtualisation program (via KVM) to add to its core RHEL operating system distribution but CEO Jim Whitehurst has long batted off suggestions that it needed to add a database or other aspects to the mix.

So why the new investment? In the press release, the companies play it straight by saying it is part and parcel of a partnership to promote complementary open-source infrastructure. Well, fine, but any such partnership has a domino effect. It's tempting to see this as a pre-emptive strike at Oracle but it is also likely to send shock waves through other open-source database vendors such as Ingres. Maybe Red Hat's next move will be to also invest and partner with those other companies, thus ensuring a healthy roster of partners; it is, after all, by far the largest and most successful company that is dependent on OSS. On the other hand, those who suspect that Red Hat will eventually sell to Oracle might suspect that this bait.

The other alternative view is that Red Hat is preparing for a U-turn that will see it join the stack players by acquiring EnterpriseDB. Whichever way things work out, this is an intriguing development.