[Python] Dealing with Automap Errors by excluding tables

I'm using SQLAlchemy's automap to autogenerate the schema from a Postgres database managed by Odoo (direct access of the database is WAAAYYY faster than using the Odoo API). But following examples from the docs are giving me problems.

I'm trying to only parse specific tables per the advice here:

# we can reflect it ourselves from a database, using options
# such as 'only' to limit what tables we look at...
metadata.reflect(engine, only=['user', 'address'])


My code:

import sqlalchemy as sa
from sqlalchemy.ext.automap import automap_base
from app import odb
from sqlalchemy.orm import declarative_base, relationship
from sqlalchemy.orm.relationships import RelationshipProperty

metadata = sa.MetaData()
metadata.reflect(odb, only=['sale_order'])
Base = automap_base(metadata=metadata)
Base.prepare()
Order = Base.classes.sale_order


But I'm erroring out on a mapping for a table that I didn't specify.

[ins] In [1]: from app.omodels import Order
/home/mas/pe/app/omodels/omodels.py:8: SAWarning: Skipped unsupported reflection of expression-based index res_partner_vat_index
metadata.reflect(odb, only=['sale_order'])
---------------------------------------------------------------------------
ArgumentError Traceback (most recent call last)
<ipython-input-1-39a04770d5b4> in <module>
----> 1 from app.omodels import Order

~/pe/app/omodels/__init__.py in <module>
----> 1 from .omodels import *

~/pe/app/omodels/omodels.py in <module>
8 metadata.reflect(odb, only=['sale_order'])
9 Base = automap_base(metadata=metadata)
---> 10 Base.prepare()
11 Order = Base.classes.sale_order
12

<string> in prepare(cls, autoload_with, engine, reflect, schema, classname_for_table, collection_class, name_for_scalar_relationship, name_for_collection_rela
tionship, generate_relationship, reflection_options)

~/pe/.venv/lib/python3.6/site-packages/sqlalchemy/util/deprecations.py in warned(fn, *args, **kwargs)
296 stacklevel=3,
297 )
--> 298 return fn(*args, **kwargs)
299
300 doc = fn.__doc__ is not None and fn.__doc__ or ""

~/pe/.venv/lib/python3.6/site-packages/sqlalchemy/ext/automap.py in prepare(cls, autoload_with, engine, reflect, schema, classname_for_table, collection_class
, name_for_scalar_relationship, name_for_collection_relationship, generate_relationship, reflection_options)
926
927 for map_config in _DeferredMapperConfig.classes_for_base(cls):
--> 928 map_config.map()
929
930 _sa_decl_prepare = True

~/pe/.venv/lib/python3.6/site-packages/sqlalchemy/orm/decl_base.py in map(self, mapper_kw)
1070 def map(self, mapper_kw=util.EMPTY_DICT):
1071 self._configs.pop(self._cls, None)
-> 1072 return super(_DeferredMapperConfig, self).map(mapper_kw)
1073
1074

~/pe/.venv/lib/python3.6/site-packages/sqlalchemy/orm/decl_base.py in map(self, mapper_kw)
990 return self.set_cls_attribute(
991 "__mapper__",
--> 992 mapper_cls(self.cls, self.local_table, **self.mapper_args),
993 )
994

<string> in __init__(self, class_, local_table, properties, primary_key, non_primary, inherits, inherit_condition, inherit_foreign_keys, always_refresh, versi
on_id_col, version_id_generator, polymorphic_on, _polymorphic_map, polymorphic_identity, concrete, with_polymorphic, polymorphic_load, allow_partial_pks, batc
h, column_prefix, include_properties, exclude_properties, passive_updates, passive_deletes, confirm_deleted_rows, eager_defaults, legacy_is_orphan, _compiled_
cache_size)

~/pe/.venv/lib/python3.6/site-packages/sqlalchemy/util/deprecations.py in warned(fn, *args, **kwargs)
296 stacklevel=3,
297 )
--> 298 return fn(*args, **kwargs)
299
300 doc = fn.__doc__ is not None and fn.__doc__ or ""
~/pe/.venv/lib/python3.6/site-packages/sqlalchemy/orm/mapper.py in __init__(self, class_, local_table, properties, primary_key, non_primary, inherits, inherit_condition, inherit_foreign_keys, always_refresh, version_id_col, version_id_generator, polymorphic_on, _polymorphic_map, polymorphic_identity, concrete, with_polymorphic, polymorphic_load, allow_partial_pks, batch, column_prefix, include_properties, exclude_properties, passive_updates, passive_deletes, confirm_deleted_rows, eager_defaults, legacy_is_orphan, _compiled_cache_size)
681 self._configure_inheritance()
682 self._configure_class_instrumentation()
--> 683 self._configure_properties()
684 self._configure_polymorphic_setter()
685 self._configure_pks()

~/pe/.venv/lib/python3.6/site-packages/sqlalchemy/orm/mapper.py in _configure_properties(self)
1439
1440 self._configure_property(
-> 1441 column_key, column, init=False, setparent=True
1442 )
1443

~/pe/.venv/lib/python3.6/site-packages/sqlalchemy/orm/mapper.py in _configure_property(self, key, prop, init, setparent)
1674
1675 if not isinstance(prop, MapperProperty):
-> 1676 prop = self._property_from_column(key, prop)
1677
1678 if isinstance(prop, properties.ColumnProperty):

~/pe/.venv/lib/python3.6/site-packages/sqlalchemy/orm/mapper.py in _property_from_column(self, key, prop)
1866 "use the 'include_properties' or 'exclude_properties' "
1867 "mapper arguments to control specifically which table "
-> 1868 "columns get mapped." % (key, self, column.key, prop)
1869 )
1870

ArgumentError: WARNING: when configuring property 'product_packaging' on mapped class stock_move->stock_move, column 'product_packaging' conflicts with property '<RelationshipProperty at 0x7fe61ba87f48; product_packaging>'. To resolve this, map the column to the class under a different name in the 'properties' dictionary. Or, to remove all awareness of the column entirely (including its availability as a foreign key), use the 'include_properties' or 'exclude_properties' mapper arguments to control specifically which table columns get mapped.


QUESTION: How can I exclude this table (or only include the tables that I want) so that SQLA doesn't go needlessly parsing tables I don't need (it also seems to take quite a while to parse this database, which is huge)?

Alternatively, how can I override this specific error so that I can access my Order object? The Error/Warning says

To resolve this, map the column to the class under a different name in the 'properties' dictionary. Or, to remove all awareness of the column entirely (including its availability as a foreign key), use the 'include_properties' or 'exclude_properties' mapper arguments to control specifically which table columns get mapped.
​

But I haven't described the schema for this table, and I don't know where to put 'exclude_properties'.

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