Traceback (most recent call last):
File "database_test.py", line 46, in <module>
from plx.db.core import *
File "../src/plx/db/core.py", line 901, in <module>
UniqueConstraint(ContainerInstance.batch_id,
ContainerAggregation.container_descriptor_id,)
File
"/home/richard/.pyenv/versions/vpak-pollux-2.7.9/lib/python2.7/site-packages/sqlalchemy/sql/schema.py",
line 2464, in __init__
ColumnCollectionMixin.__init__(self, *columns, _autoattach=_autoattach)
File
"/home/richard/.pyenv/versions/vpak-pollux-2.7.9/lib/python2.7/site-packages/sqlalchemy/sql/schema.py",
line 2393, in __init__
self._check_attach()
File
"/home/richard/.pyenv/versions/vpak-pollux-2.7.9/lib/python2.7/site-packages/sqlalchemy/sql/schema.py",
line 2429, in _check_attach
table.description)
sqlalchemy.exc.ArgumentError: Column(s)
'container_aggregation.fk_container_descriptor_id' are not part of table
'container_instance'.
I got sqlalchemy from git, today. >>> sqlalchemy.__version__ '1.0.0'container_aggretation is a subclass of container_instance. I'm not using concrete inheritance here, may this be the problem?
anything else, it's Python 2.7.9 + Linux + PostgreSQL 9.4.1. cheers, richard. On 03/24/2015 08:49 PM, Michael Bayer wrote:
are these two separate constraints? I just looked and it seems like they are distinct. I just added a fix to 1.0 because someone was hacking around something similar to this. The easiest way to get these for the moment is just to create the UniqueConstraint outside of the class definition. class Foo(Base): # … class Bar(Foo): # … UniqueConstraint(Bar.x, Foo.y) that way all the columns are set up, should just work. Richard Gerd Kuesters | Pollux <rich...@pollux.com.br> wrote:well, understanding better the docs for column conflicts, can i use a declared_attr in a unique constraint? if yes, my problem is solved :) On 03/24/2015 10:33 AM, Michael Bayer wrote:Richard Gerd Kuesters | Pollux <rich...@pollux.com.br> wrote:hi all! i'm dealing with a little problem here. i have a parent table and its two inheritances. there is a value that both children have and must be unique along either types. is there a way to move this column to the parent and use a constraint in the child? my implementation is postgres 9.4+ with psycopg2 only.if this is single table inheritance then the constraint would most ideally be placed on the parent class. if you’re trying to make this “magic” such that you can semantically keep the unique constraints on the child classes, you’d need to build out a conditional approach within @declared_attr. IMO I think this is an idealized edge case that in the real world doesn’t matter much - just do what works (put the col / constraint on the base). the approach is described at http://docs.sqlalchemy.org/en/rel_0_9/orm/extensions/declarative/inheritance.html#resolving-column-conflicts . You’d need to make this work for both the column and the constraint.as a simple example (i'm just creating this example to simplify things), this works: ____________ class MyParent(Base): foo_id = Column(Integer, Sequence('foo_id_seq'), primary_key=True) foo_name = Column(Unicode(64), nullable=False) foo_type = Column(Integer, nullable=False) __mapper_args__ = { "polymorphic_on": foo_type, "polymorphic_identity": 0 } class MyChild1(MyParent): foo_id = Column(Integer, ForeignKey(MyParent.foo_id), primary_key=True) bar_id = Column(Integer, ForeignKey(AnotherEntity.bar_id), nullable=False) child1_specific_name = Column(Unicode(5), nullable=False) child1_baz_stuff = Column(Boolean, default=False) __mapper_args__ = { "polymorphic_identity": 1 } __table_args__ = ( UniqueConstraint(bar_id, child1_specific_name,), # works, bar_id is in MyChild1 ) class MyChild2(MyParent): foo_id = Column(Integer, ForeignKey(MyParent.foo_id), primary_key=True) bar_id = Column(Integer, ForeignKey(AnotherEntity.bar_id), nullable=False) child2_specific_code = Column(UUID, nullable=False) child2_baz_stuff = Column(Float, nullable=False)__mapper_args__ = {"polymorphic_identity": 2 } __table_args__ = ( UniqueConstraint(bar_id, child2_specific_code,), # works, bar_id is in MyChild2 ) ____________ but i would like to do this, if possible: ____________ class MyParent(Base): foo_id = Column(Integer, Sequence('foo_id_seq'), primary_key=True) foo_name = Column(Unicode(64), nullable=False) foo_type = Column(Integer, nullable=False) bar_id = Column(Integer, ForeignKey(AnotherEntity.bar_id), nullable=False) # since both child uses bar_id, why not having it on the parent? __mapper_args__ = { "polymorphic_on": foo_type, "polymorphic_identity": 0 } class MyChild1(MyParent): foo_id = Column(Integer, ForeignKey(MyParent.foo_id), primary_key=True) child1_specific_name = Column(Unicode(5), nullable=False) child1_baz_stuff = Column(Boolean, default=False) __mapper_args__ = { "polymorphic_identity": 1 } __table_args__ = ( UniqueConstraint(MyParent.bar_id, child1_specific_name,), # will it work? ) class MyChild2(MyParent): foo_id = Column(Integer, ForeignKey(MyParent.foo_id), primary_key=True) child2_specific_code = Column(UUID, nullable=False) child2_baz_stuff = Column(Float, nullable=False)__mapper_args__ = {"polymorphic_identity": 2 } __table_args__ = ( UniqueConstraint(MyParent.bar_id, child2_specific_code,), # will it work? ) ____________ well, will it work without being a concrete inheritance? :) best regards, richard. -- You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To unsubscribe from this group and stop receiving emails from it, send an email to sqlalchemy+unsubscr...@googlegroups.com . To post to this group, send email to sqlalchemy@googlegroups.com . Visit this group at http://groups.google.com/group/sqlalchemy . For more options, visit https://groups.google.com/d/optout .-- You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To unsubscribe from this group and stop receiving emails from it, send an email to sqlalchemy+unsubscr...@googlegroups.com. To post to this group, send email to sqlalchemy@googlegroups.com. Visit this group at http://groups.google.com/group/sqlalchemy. For more options, visit https://groups.google.com/d/optout.
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