Patrick Eugene O'Neil is an American computer scientist, an expert on databases, and a professor of computer science at the University of Massachusetts Boston. O'Neil did his undergraduate studies at the Massachusetts Institute of Technology, receiving a B.S. in mathematics in 1963. After earning a masters' degree at the University of Chicago, he moved to Rockefeller University, where he earned a Ph.D. in combinatorial mathematics in 1969 under the supervision of Gian-Carlo Rota. He was an assistant professor at MIT from 1970 to 1972, but then left academia for industry, returning in 1988 as a member of the UMass/Boston faculty. He became a full professor in 1996. O'Neil has written highly cited papers on replication in distributed databases, page replacement strategies for databases, SQL isolation, and database indexing strategies. With Elizabeth J. O'Neil, he is the author of the database textbook Database Principles, Programming, and Performance. Prof. O'Neil produced the first commercial implementation of bitmap indices in the Model 204 DBMS in the early 1980s. This work was first published in 1987. [More at Wikipedia]