22. The system of claim 17 , wherein the context-updating mechanism additionally stores the concept-mapping function as an array of data values that maps attribute values to corresponding numerical compatibility indices.
17. A system for updating a concept-mapping function that facilitates evaluating a qualitative search term applied to an attribute during query processing, the method comprising: at least one processor and at least one associated memory; and a context-updating mechanism that executes on the at least one processor and is configured to: extract a value for the attribute from each data item in a set of data items; and update the concept-mapping function based on the extracted attribute values, wherein the concept-mapping function associates a given value for the attribute with a numerical compatibility index that indicates a compatibility between the given value and the qualitative search term as applied to the attribute, wherein the qualitative search term comprises one or more words that express a quality of the attribute value; wherein while updating the concept-mapping function, the context-updating mechanism: determines boundaries for the concept-mapping function based the extracted attribute values, and within the determined boundaries, uses a pre-specified distribution to update the concept-mapping function; and wherein while determining the boundaries for the concept-mapping function, the context-updating mechanism: computes a mean attribute value and a standard deviation for the extracted attribute values; and uses the mean attribute value and the standard deviation to determine the boundaries for the concept-mapping.