1. A computer-executed method, comprising: receiving in a structured database having at least one table, each table containing a respective plurality of tuples, a logical query from a requestor, the logical query expressing at least one logical condition on data; responsive to receiving in said structured database the logical query from the requestor, forwarding the logical query from said structured database to a stream computing application, said stream computing application producing output tuples, each output tuple for inclusion in a respective table of said structured database; responsive to receiving, in said stream computing application, the forwarded logical query from said structured database, searching in-flight data in said stream computing application to identify selective in-flight data of said stream computing application matching the at least one logical condition of the forwarded logical query; returning results of the forwarded logical query from said stream computing application to said structured database, the results of the forwarded logical query being derived from the selective in-flight data matching the at least one logical condition of the forwarded logical query, the results of the forwarded logical query being separate from the output tuples produced by said stream computing application for inclusion in one or more respective tables of said structured database; and returning, from said structured database to said requestor, query results of the logical query received from the requestor, said query results including data derived from the selective in-flight data matching the at least one logical condition of the forwarded logical query.