Parsing multi term search string into query spec?

I'm working on a web service that allows users to search for appointments with businesses contained in our index. We intend to make an intelligent search engine which would handle multiple types of terms. The basic goal is to parse a string such as "dentist next week night bay area" or subsets of it, into 4 categories: service type, date range, time range , and location. We can then use those categories to build a query for our database.

I'm a strong believer in buying vs building, but I've been having trouble finding any products that offer this capability. Is this a featur开发者_如何学编程e most companies develop in-house? Thanks for any advice.

You are talking semantic analysis, it is a broad subject

There is a python toolkit nltk which can do categorization of text.

The classifier might be more appropriate