Optimizing query performance in virtual database

A computer program product comprising:

• a computer readable storage medium readable by one or more processors and storing instructions for execution by the one or more processors for performing a method comprising:
• collecting real time system statistics on a system environment in a remote platform running a remote data source amongst a plurality of remote data sources of a virtual database, wherein the remote data sources of the virtual database are heterogeneous database management systems run on respective remote platforms across disparate geographical locations;
• gathering real time data source statistics on one or more data source objects from the remote data source of the virtual database;
• updating a global catalog of the virtual database with the real time system statistics from the collecting and the real time data source statistics from the gathering;
• optimizing an access plan to process a query submitted to the virtual database from a client application based on the real time system statistics and the real time data source statistics in the global catalog;
• and
• producing a response corresponding to the query by executing the access plan to thereby improve both a response time of the query and a cost of processing.

A system comprising:

• a memory;
• one or more processors in communication with the memory;
• and
• program instructions executable by the one or more processors via the memory to perform a method comprising:
• collecting real time system statistics on a system environment in a remote platform running a remote data source amongst a plurality of remote data sources of a virtual database, wherein the remote data sources of the virtual database are heterogeneous database management systems run on respective remote platforms across disparate geographical locations;
• gathering real time data source statistics on one or more data source objects from the remote data source of the virtual database;
• updating a global catalog of the virtual database with the real time system statistics from the collecting and the real time data source statistics from the gathering;
• optimizing an access plan to process a query submitted to the virtual database from a client application based on the real time system statistics and the real time data source statistics in the global catalog;
• and
• producing a response corresponding to the query by executing the access plan to thereby improve both a response time of the query and a cost of processing.