C-Phrase: A system for building robust natural language interfaces to databases

This article presents C-Phrase, a natural language interface system that can be configured by normal, non-specialized, web-based technical teams. C-Phrase models queries in an extended version of Codd’s tuple calculus and uses synchronous context-free grammars with lambda-expressions to represent semantic grammars. Given an arbitrary relational database, authors rapidly build an NLI using what we term the name-tailor-define protocol. We present a small study demonstrating the effectiveness of this approach for the GEO corpus and we introduce the evaluation metric of willingness that complements the standard metrics of precision and recall. However our true evaluation comes as we open-source C-Phrase.