Using boolean circuits for the parallel computation of queries

We present partial results of a research project in which we use boolean circuits as a parallel computation model for the expression of queries to relational databases. For that purpose, we use the well-known equivalence between First Order Logic (FO) and a class of restricted families of boolean circuits. First, we translate a given query, expressed through a FO formula, into a uniform family of boolean circuits. Then we analyse the depth of the boolean circuits, in order to optimize parallel time. For this sake, we work on the expression tree of the formula, looking for its transformation into an equivalent family of boolean circuits of minimum depth.