Abstract: Systems and methods are presented for building comprehensive entity knowledgebases that can consolidate multiple linked references to the same entity. The resulting virtual repository can be efficiently queried. An incoming record is clustered into entities, which are collections of attributes. The system can determine the entity that most closely matches an incoming record. Coarse-grain representations (blocking) may be used initially to select a set of the most closely-matching entities, and then fine-grain representations (linkage) may be used. Coarse-grain and fine-grain match probabilities may be integrated to obtain integrated match probabilities between the record and each of the closest-matching entities. Entities are updated, including creating a new entity, merging two or more entities into one, dividing one entity, and making no change in the entities, after which the record is entered into the appropriate entity or entities. Embodiments support both free-form querying and document matching.