ORM code example for a query of a single table

[SF Markus Elfring]

Hello,

I would like to query a single table by the ORM interface
for an export of the stored data into an other file format.

The description of the query API refers also to the object
relational tutorial. This tutorial explains also functionality
which deals with table creation. I imagine that I can omit
a few statements (like "Base.metadata.create_all(engine)")
there if I want to concentrate on a specific data selection.

How many meta-data will I need to add to the corresponding
class so that the declarative mapping will work for an
existing database table?
Will table properties be automatically mapped into the
provided Python class (without explicit specifications)?

Regards,
Markus

[Jonathan Vanasco]

Take a look at sqlacodegen

    https://pypi.python.org/pypi/sqlacodegen/

It can build the Python classes (sqlalchemy declarative) from your existing database.