A system and methods rank results of database queries. An automated approach for ranking database query results is disclosed that leverages data and workload statistics and associations. Ranking functions are based upon the principles of probabilistic models from Information Retrieval that are adapted for structured data. The ranking functions are encoded into an intermediate knowledge representation layer. The system is generic, as the ranking functions can be further customized for different applications. Benefits of the disclosed system and methods include the use of adapted probabilistic information retrieval (PIR) techniques that leverage relational/structured data, such as columns, to provide natural groupings of data values. This permits the inference and use of pair-wise associations between data values across columns, which are usually not possible with text data.