Witold Lipski Jr. (July 13, 1949, in Warsaw, Poland – May 30, 1985, in Nantes, France) was a Polishcomputer scientist (habilitation in computer science), and an author of two books:Combinatorics for Programmers (two editions) and (jointly with Wiktor MarekCombinatorial analysis. Lipski, jointly with his PhD student, Tomasz Imieliński, createdfoundations of the theory of incomplete information in relational databases.