Hello Michael,

2010/8/18 Michael Hipp <[email protected]>:
> <snip>
> Is this a typical/expected difference in performance between the two query
> methods?
> <snip code>

Yes. This is expected. When you use the ORM, SQLAlchemy has to
instantiate Python objects and populate each property from the result
set (and maybe more objects from relations). That takes some time.

That doesn't happen when using "SQL Expression Language" as what you
get back is basically a bunch of tuples for every result set. It's
lower level than the ORM (the ORM actually sits on top of the
Expression Language system).

And, quite recently, some part of the SQL Expression Language layer
has gain a C extension (not enabled by default). So you may gain some
little improvement using the ORM (~20%), but the using the Expression
Languages system itself should be much faster.

-- 
Alex
twitter.com/alexconrad

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