Memory-efficient XML parser that yields Ruby objects

What I wanted to achieve is to take advantage of SAX parser (memory efficiency when used correctly) with as little preconfiguration as possible, because I often face one-off tasks that involve importing large XML files into database.

I've seen some implementations of SAX parsers, but they either missed the point by only using it's API under the hood and still returning all the results at once (thus not being memory-efficient at all) or required extensive configuration (which seems a waste for one-off imports).