Computer Science professor at the University of Wisconsin Madison. Expert in databases. Pissed off Larry Ellison some time around 1980 when he published benchmark results that showed Oracle in a bad light. Ellison wrote the university and demanded DeWitt's removal. For years, Ellison refused to hire any graduates from UW-Madison because of DeWitt's publication.

Today, he says that his two biggest regrets are publishing his benchmark results, and not buying up Oracle stock right after he single-handedly caused it to crash.