1. A computer-implemented method for transforming a query, comprising: generating a transformed query for the query, wherein: the query includes a first subquery and a second subquery; both the first subquery and the second subquery are EXISTS subqueries; and generating the transformed query comprises coalescing the first subquery and the second subquery into a single subquery by eliminating either the first subquery or the second subquery and not replacing the eliminated subquery with any subquery.