Memory-efficient iteration

[ADanilychevJr]

Been loving django-pandas so far!

One issue I've been having is with python eating up way too much memory for some of my larger tables. Once read in, a dataframe I have is only 2.1MB, built from around 150k rows. I'm getting memory quota errors on Heroku due to this.

A more memory-efficient iteration for io.read_frame would be great
Something like this: http://www.poeschko.com/2012/02/memory-efficient-django-queries/