Spyced

I presented at the utah python user group last night. I gave an introduction to the PyDO2 ORM tool as well as the python DB API and psycopg. Most readers are probably most interested in the pydo2 section. Here's the slides: http://utahpython.org/data/python-and-databases.pdf . I briefly mentioned SqlAlchemy in the context of, "here's some stuff that SqlAlchemy does that pretty much nobody else can," but didn't have time to cover TWO ORM tools. It's worth having a look at though if you've reached the limits of what pydo2 et al can do.

Take Alex Martelli's Number class from the augmented assignment example in What's New in Python 2.0 : class Number: def __init__(self, value): self.value = value def __iadd__(self, increment): return Number( self.value + increment) >>> n = Number(5) >>> n That's not very pretty. Let's add a __getattr__ method and leverage all those nice methods from the int or float or whatever it's initialized with: class Number: def __init__(self, value): self.value = value def __iadd__(self, increment): return Number( self.value + increment) def __getattr__(self, attr): return getattr(self.value, attr) >>> n = Number(5) >>> n 5 Great, the __str__ method from our int is being used. Let's keep going with the example now: >>> n += 3 >>> n.value Traceback (most recent call last): File " ", line 1, in ? AttributeError: 'int' object has no att...

Glyph Lefkowitz cites me as an inspiration to write Why Axiom Doesn't Expose SQL . Alas, I disagree with most of what he says. My post was about how if you're writing a tool that presupposes the use of a relational database, it's stupid to try to protect your users from having to know SQL . (This also means I think projects that bend over backwards to pretend ALTER TABLE is too hard are misguided, as well. But that's another subject.) Glyph's first argument is that any form of SQL is an invitation to sql injection attacks. This particular form of scare mongering isn't appreciated. Come on: this is 2005. It's ridiculously easy to write injection-proof SQL, even by hand. Arguing that allowing SQL allows injection attacts is like arguing that coding in python allows "shutil.rmtree('/')": correct, but irrelevant. Glyph further claims that "interfaces should be complete things," and that this justifies trying to obliterate any ...