A method, computer program and database system are disclosed for joining a plurality of tables T1 through TN, where each of the tables has an associated Star Map, S1 through SN, respectively. Each Star Map includes bitmap entries having locations indexed by the hash of one or more values associated with...http://www.google.com.hk/patents/US7092954?utm_source=gb-gplus-share專利 US7092954 - Optimizing an equi-join operation using a bitmap index structure
