A system and method for improving performance of join operations is disclosed. The method in one embodiment includes building a graph of vertices and edges, which represent the tables and join conditions for a particular database schema. The method then traverses the graph to find a set of candidate join operations. The method further includes selecting from the set of subset of join operations that makes the best use of a given amount of memory, which means finding a collection of denormalizations which when residing in memory provide the most benefit and the least cost for the given amount of memory. The method then deploys the denormalizations so that current queries in a query processing system can use them instead of actually performing the joins.