Generating Queries Using Cardinality Constraints

At least one computer-readable medium having one or more executable instructions that, when read, cause one or more processors to:

• (a) create a set of initial parameters based on a structure of a pattern query;
• (b) derive at least one set of candidate parameters for the pattern query based on at least a step size;
• (c) evaluate, against a database, the pattern query using each sub-set of candidate parameters respectively corresponding to each of the at least one set of candidate parameters;
• (d) select the sub-set of candidate parameters that produce the smallest deviation from a predetermined cardinality relative to the remainder of the sub-sets of candidate parameters;
• (e) divide the step size by a predetermined value;
• and
• (f) repeat (b)-(e) a predetermined number of times for a particular refinement model.

A system, comprising:

• a database to store data;
• a query generator to generate at least one set of parameters for a pattern query returning a predetermined number of results from the database based on a particular refinement model;
• and
• a query evaluation layer to perform the pattern query using the at least one set of parameters.