Profiling data includes processing an accessed collection of records, including: generating, for a first set of distinct values appearing in a first set of one or more fields, corresponding location information; generating, for the first set of fields, a corresponding list of entries identifying a distinct value from the first set of distinct values and the location information for the distinct value; generating, for a second set of one or more fields, a corresponding list of entries, with each entry identifying a distinct value from a second set of distinct values appearing in the second set of fields; and generating result information, based at least in part on: locating at least one record of the collection using the location information for at least one value appearing in the first set of fields, and determining at least one value appearing in the second set of fields of the located record.