ContinuumIO/blaze — pull request #335 by mrocklin (2014-06-16 17:25:22+00:00)
Title: use instance for sqlalchemy type checking

Looks like sqlalchemy has a hierarchy for the various dtypes. We use instance to help deal with this. This was relevant when dealing with Postgres rather than sqlite. Postgres has its own dialect.

We might want to worry about the order of checking with isinstance at some point.