Yeah I have been testing out symphony with the aim of just using it as a persistence framework, and using an external JavaScript library for the UI I don't plan on using any symfony front-end features.
Basically you define your database tables and attribute in a YAML (
YAML - Wikipedia, the free encyclopedia) format, it then generates the schema and the PHP persistence files allowing you to retrieve, add, update and delete records.
So far, I think it's a quite intuitive and easy to use framework even though it's command based, the documentation is excellent, that's what makes it so easy to follow. I recommend you walk through the sample project it'll give you a good idea of how symfony works.
I'll post more if I ever return to my little project