The Dynamic Descriptive Complexity of k-Clique

Abstract

In this work the dynamic descriptive complexity of the k-clique query is studied. It is shown that when edges may only be inserted then k-clique can be maintained by a quantifier-free update program of arity k-1, but it cannot be maintained by a quantifier-free update program of arity k-2 (even in the presence of unary auxiliary functions). This establishes an arity hierarchy for graph queries for quantifier-free update programs under insertions. The proof of the lower bound uses upper and lower bounds for Ramsey numbers.

An extended abstract of this work appeared in the proceedings of the conference Mathematical Foundations of Computer Science 2014 (MFCS 2014)