1. A method of establishing a sampled query of tables in a database, the method comprising the steps of: a) generating a subset of entries based on a query for data from the tables, the entries representing elements of an index of a larger table from the tables of the query; b) generating a sampling predicate to reduce the number of entries in the subset, the sampling predicate being obtained from the query; c) applying the sampling predicate to the subset to reduce the number of entries in the subset; and d) generating a search of the reduced subset based on the query.