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PyCon: SQLAlchemy 0.4 and Beyond

SQLAlchemy 0.4 and Beyond

This was a whirlwind talk by Mike Bayer that covered both the past and the future of features in SQLAlchemy. It was good, but I'd need about three times as much time in order to understand it all.

0.1 was released in 2006.

0.4 will be faster and have better, smarter support for transactions.

SQLAlchemy now has crazy SQL generators for all sorts of weird situations. Inheritance is the least of these. There are tons of weird tricks that SQLAlchemy can automate for you.

SQLAlchemy now has a new "declarative" layer. You can use it if you don't want to go as far as Elixir goes. It's pretty simple. I think it's only 90 lines of code, or something like that. It unifies the tables and the classes.

SQLAlchemy provides lots and lots of abstraction. For me, at least, it's helpful to step back and look at what the SQL is really doing.

SQLAlchemy now has support for transaction sessions and transaction nesting (i.e. savepoints). However, it doesn't know how to rollback in-memory object state yet.

It also has support for two-phase commits. Use this if you need to commit a transaction to multiple databases.

It has support for lots of databases.

It now has some horizontal sharding support, modeled after Hibernate.

Support for migrating your database schema using Python syntax is now back.

There are multiple SQLAlchemy books on the way.


mike bayer said…
I didn't think the SQL examples in the talk were particularly crazy. I went through them too quick in the talk for sure but at the end of the day every example was pretty much joining two or three tables together on their foreign keys and adding some criterion.
I'm sure you're right. I just can't read that fast.

I'm just emphasizing that SQLAlchemy has become pretty sophisticated.