Amit Singh spent 20 years at Oracle. Then he left for the clouds.

MOUNTAIN VIEW, Calif. — Amit Singh defected to Google after 20 years at Oracle because he wanted to join the revolution in the cloud. In May, he took over Google’s enterprise operations, overseeing the company’s effort to replace traditional business software with new-age web services such as Google Apps and Google App Engine. Since his move, Oracle has uncloaked its own “cloud” services. But for Singh, that’s a little different.

“I don’t know what there is about Oracle’s cloud that is really the cloud,” he told Wired.com this we...