Larry Ellison is a famously activist exponent of competitive strategy. An avowed student of Sun Tzu’s Art of War, the Oracle chief executive has long followed an approach that sets Oracle’s interests against those of its main rivals, with Microsoft, IBM and SAP cast as the enemy.

With the acquisition of Sun Microsystems, however, he is about to walk on to new terrain where some of the methods that defined Oracle’s traditional approach to strategy no longer apply.