Querying In-Flight Streamed Data from a Relational Database

A non-transitory computer-readable media having recorded thereon a computer program having a plurality of computer-executable instructions, wherein the computer program, when executed by at least one computer system, causes the at least one computer system to perform actions comprising:

• receiving in a structured database having at least one table, each table containing a respective plurality of tuples, a request from a requestor to execute a logical query, the logical query expressing at least one logical condition on data;
• responsive to receiving said request to execute the logical query, 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.

A data processing apparatus supporting execution of a stream computing application, comprising:

• at least one physical processor;
• at least one physical memory;
• a stream computing application embodied as instructions executable on the at least one processor and storable in the at least one memory, the stream computing application implementing an operator graph having a plurality of processing elements which operate on data tuples being transferred among processing elements of the plurality of processing elements, the stream computing application producing output tuples, each output tuple for inclusion in a respective table of a structured database having at least one table, each table containing a respective plurality of tuples;
• at least one database agent associated with the stream computing application, the at least one database agent embodied as instructions executable on the at least one processor and storable in the at least one memory, wherein the at least one database agent:
• receives a forwarded logical query from said structured database, the forwarded logical query expressing at least one logical condition on data;
• responsive to receiving the forwarded logical query from said structured database, searches in-flight data of said stream computing application to identify selective in-flight data matching the at least one logical condition of the forwarded logical query;
• and;
• returns results of the forwarded logical query to said structured database, the results of the forwarded logical query being derived from the 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 said output tuples produced by said stream computing application for inclusion in one or more respective tables of said structured database.