Natural-language database interface with automated keyword mapping and join-path inferences

摘要

A natural language interface for databases (NLIDB) component of a database-management system receives a user-submitted natural-language query. The NLIDB parses the query into keywords and maps each keyword onto a corresponding query fragment that identifies a predicate of a non-join condition, or other type of expression, of a structured query. The NLIDB selects an optimal mapping for each keyword with the aid of a Query Fragment Graph (QFG) that counts the number of occurrences of each fragment, and the number of co-occurrences of each pair of fragments, in previously received structured queries. The NLIDB then uses the QFG, optionally augmented by contextual data, to select join paths most likely to be consistent with the semantic intent of the user. The NLIDB generates a structured query that incorporates the mapped query fragments and selected join paths and forwards. The structured the query is then forwarded to downstream DBMS components.