UI Prototype Tool with Database Backing?

Hello everyone! Hopefully posting in the right place.

I have a client requesting a click-through prototype (like Axure) of a web-based application before they will agree to a project. However, they also want the prototype to have "proof of concept", so that the data within the fields of the prototype wouldn't be hard-coded, but instead filled with realistic data from 15 objects.

I have asked everyone at my company and searched everywhere, and cannot find a tool that would fit these requirements. Can anyone think of something that sounds similar? Thank you so much!!