Correction on wordings:
One parent table, two child tables, one foreign key from each child
pointing to the same field in parent with "one to one relationship" works
with no problem, but getting "AmbiguousForeignKeysError" as soon as adding
the second foreign key to child tables pointing to the second field in
parent. tried various combinations but none has worked so far. specifically
tring to add foreign_keys as suggested in error message.
Here is the code that throwing error.
class Parent(Base):
__tablename__ = 'parent'
field_one = Column(String(256),
unique=True,
nullable=False,
primary_key=True)
field_two = Column(String(128),
nullable=False,
primary_key=True)
p_child_one_fields = relationship("ChildOne",
uselist=False,
passive_deletes=True,
backref=backref("ref_to_parent_field_one",
foreign_keys="[ChildOne.field_one,
ChildOne.field_two]"),
cascade="all, delete-orphan")
p_child_two_fields = relationship("ChildTwo",
uselist=False,
passive_deletes=True,
backref=backref("ref_to_parent_field_two",
foreign_keys="[ChildTwo.field_one,
ChildTwo.field_two]"),
cascade="all, delete-orphan")
class ChildOne(Base):
__tablename__ = 'child_one'
field_one = Column(String(256),
ForeignKey('parent.field_one',
onupdate="CASCADE",
ondelete='CASCADE'),
unique=True,
nullable=False,
primary_key=True)
field_two = Column(String(256),
ForeignKey('parent.field_two',
onupdate="CASCADE",
ondelete='CASCADE'),
unique=True,
nullable=False,
primary_key=True)
class ChildTwo(Base):
__tablename__ = 'child_two'
field_one = Column(String(256),
ForeignKey('parent.field_one',
onupdate="CASCADE",
ondelete='CASCADE'),
unique=True,
nullable=False,
primary_key=True)
field_two = Column(String(256),
ForeignKey('parent.field_two',
onupdate="CASCADE",
ondelete='CASCADE'),
unique=True,
nullable=False,
primary_key=True)
Any suggestion to fix the problem will be appreciated.
Do I need to have 4 relationships or can be done with two relationships ?
Thank you
On Sat, 30 May 2020 at 18:13, Sydo Luciani <sydo.luci...@gmail.com> wrote:
>
> One parent table, two child tables, two foreign keys pointing to a field
> in parent with "one to one relationship" works with no problem, but getting
> "AmbiguousForeignKeysError" as soon as adding the second foreignkey to
> child table. tried various combinations but none has worked so far.
> specifically tring to add foreign_keys as suggested in error message.
>
> Here is the code that throwing error.
>
> class Parent(Base):
> __tablename__ = 'parent'
>
> field_one = Column(String(256),
> unique=True,
> nullable=False,
> primary_key=True)
>
> field_two = Column(String(128),
> nullable=False,
> primary_key=True)
>
> p_child_one_field_one = relationship("ChildOne",
> uselist=False,
> passive_deletes=True,
> backref=backref("ref_to_parent_field_one",
> foreign_keys="[ChildOne.field_one,
> ChildOne.field_two]"),
> cascade="all, delete-orphan")
>
> p_child_two_field_one = relationship("ChildTwo",
> uselist=False,
> passive_deletes=True,
> backref=backref("ref_to_parent_field_two",
> foreign_keys="[ChildTwo.field_one,
> ChildTwo.field_two]"),
> cascade="all, delete-orphan")
>
>
>
> class ChildOne(Base):
> __tablename__ = 'child_one'
>
> field_one = Column(String(256),
> ForeignKey('parent.field_one',
> onupdate="CASCADE",
> ondelete='CASCADE'),
> unique=True,
> nullable=False,
> primary_key=True)
>
> field_two = Column(String(256),
> ForeignKey('parent.field_two',
> onupdate="CASCADE",
> ondelete='CASCADE'),
> unique=True,
> nullable=False,
> primary_key=True)
>
>
> class ChildTwo(Base):
> __tablename__ = 'child_two'
>
> field_one = Column(String(256),
> ForeignKey('parent.field_one',
> onupdate="CASCADE",
> ondelete='CASCADE'),
> unique=True,
> nullable=False,
> primary_key=True)
>
> field_two = Column(String(256),
> ForeignKey('parent.field_two',
> onupdate="CASCADE",
> ondelete='CASCADE'),
> unique=True,
> nullable=False,
> primary_key=True)
>
>
> Any suggestion to fix the problem will be appreciated.
>
> Thank you
>
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