3. The method of claim 1 , including a query server that identifies where each of a plurality of compiled skeletal queries are located, and determining whether the compiled skeletal query is available at the target database server includes querying the query server.
1. A method comprising: receiving, at a processing system that includes a processor and memory, a user query for selecting data from a database that is accessible via a plurality of database servers; parsing, by the processing system, the user query to identify a skeletal query form corresponding to the user query and one or more arguments associated with the user query, and to identify a target database server among the plurality of database servers based on the skeletal query form and the one or more arguments; determining, by the processing system, whether a compiled skeletal query corresponding to the identified skeletal query form is available at the target database server, the compiled skeletal query including machine code that is executable directly by the processing system, and, if the compiled skeletal query is available at the target database server: communicating, by the processing system, the user query and one or more arguments associated with the user query to the target database server; retrieving, by the target database server, the machine code corresponding to the compiled skeletal query from a database; executing, by the target database server, the machine code using the one or more arguments associated with the user query; and providing, from the target database server, results of the executing of the machine code in response to the user query; and if the compiled skeletal query is not available at the target database server: providing the compiled skeletal query to the target database server.