This paper resolves the main open question left by Gottlob, Lee, and Valiant
(PODS 2009)[GLV09], establishing tight worst-case bounds for the size of the
result Q(D) of a conjunctive query Q to a database D given an arbitrary set of
functional dependencies. We show that the lower bound presented in [GLV09] in
which the variables of the query are "colored" so as to yield a coloring number
C(Q) for each query Q is, in fact, also an upper bound.