Right, so it would start something like this:
class Contact(db.Model):
__tablename__ = 'contact'
id = db.Column(db.Integer, primary_key=True)
name = db.Column(db.Unicode(120), nullable=False, unique=False)
created_on = db.Column(db.DateTime, default=datetime.utcnow)
birthday = db.Column(db.DateTime)
background = db.Column(db.Text)
photo = db.Column(db.Unicode(120))
user_id = db.Column(db.Integer, db.ForeignKey('user.id'))
to_contacts = association_proxy('to_relations', 'to_contact')
from_contacts = association_proxy('from_relations', 'from_contact')
class ContactRelation(db.Model):
__tablename__ = 'contactrelation'
id = db.Column(db.Integer, primary_key=True)
from_contact_id = db.Column(db.Integer, db.ForeignKey('contact.id'))
to_contact_id = db.Column(db.Integer, db.ForeignKey('contact.id'))
relation_type = db.Column(db.String(100), nullable=True)
from_contact = db.relationship(Contact,
primaryjoin=(from_contact_id == Contact.id),
backref='to_relations')
to_contact = db.relationship(Contact,
primaryjoin=(to_contact_id == Contact.id),
backref='from_relations')
Hope that helps,
Simon
On Wed, Sep 24, 2014 at 8:27 PM, Mohammad Reza Kamalifard
<mr.kamalif...@gmail.com> wrote:
>
> Thanks,
> I want to create a relationship between two contact object and add more data
> like relation type to the relation table.
> For example Contact with contact id 1 and contact id 2 has friend
> relationship type and some more data.
> Exactly i want a self association relation.
>
>
>
> On Wed, Sep 24, 2014 at 7:47 PM, Simon King <si...@simonking.org.uk> wrote:
>>
>> OK, firstly I'm not sure you want to be using your contactrelation
>> table both as a "secondary" as well as a mapped class. You generally
>> want one or the other. See the note at the bottom of the "Association
>> Object" section of
>>
>> http://docs.sqlalchemy.org/en/rel_0_9/orm/relationships.html#association-object
>>
>> For your specific error, you could try defining the primaryjoin and
>> secondaryjoin conditions like this, but I've honestly no idea if it is
>> the right approach:
>>
>> primaryjoin=id=='foreign(contactrelation.c.from_contact_id)',
>> secondaryjoin=id=='foreign(contactrelation.c.to_contact_id)',
>>
>> This definitely seems fishy to me though - I'm not sure if SA will
>> understand that the 2 "id" columns there correspond to 2 different
>> instances of the Contact class.
>>
>> Unless you have a particular need for the "secondary" mechanism, I
>> would rewrite it so that ContactRelation has "from_contact" and
>> "to_contact" relationships, then use an association proxy to hide the
>> ContactRelation when you don't need it explicitly:
>>
>> http://docs.sqlalchemy.org/en/rel_0_9/orm/extensions/associationproxy.html
>>
>>
>> Hope that helps,
>>
>> Simon
>>
>>
>> On Wed, Sep 24, 2014 at 2:15 PM, Mohammad Reza Kamalifard
>> <mr.kamalif...@gmail.com> wrote:
>> > Here is the whole Contact and ContactRelation model
>> > class Contact(db.Model):
>> > __tablename__ = 'contact'
>> > id = db.Column(db.Integer, primary_key=True)
>> > name = db.Column(db.Unicode(120), nullable=False, unique=False)
>> > created_on = db.Column(db.DateTime, default=datetime.utcnow)
>> > birthday = db.Column(db.DateTime)
>> > background = db.Column(db.Text)
>> > photo = db.Column(db.Unicode(120))
>> > user_id = db.Column(db.Integer, db.ForeignKey('user.id'))
>> >
>> > to_contacts = db.relationship('Contact',
>> > secondary='contactrelation',
>> > primaryjoin=id== 'contactrelation.c.from_contact_id',
>> > secondaryjoin=id== 'contactrelation.c.to_contact_id',
>> > backref = 'from_contacts')
>> >
>> > class ContactRelation(db.Model):
>> > __tablename__ = 'contactrelation'
>> > id = db.Column(db.Integer, primary_key=True)
>> > from_contact_id = db.Column(db.Integer, db.ForeignKey('contact.id'))
>> > to_contact_id = db.Column(db.Integer, db.ForeignKey('contact.id'))
>> > relation_type = db.Column(db.String(100), nullable=True)
>> >
>> >
>> > Thanks,
>> >
>> > Mohammad Reza
>> >
>> >
>> > On Wed, Sep 24, 2014 at 2:38 PM, Simon King <si...@simonking.org.uk>
>> > wrote:
>> >>
>> >> Could you show the whole model and table definition? I've lost track
>> >> of exactly what you've written.
>> >>
>> >> Thanks,
>> >>
>> >> Simon
>> >>
>> >> On Wed, Sep 24, 2014 at 11:15 AM, Mohammad Reza Kamalifard
>> >> <mr.kamalif...@gmail.com> wrote:
>> >> > thanks Mike
>> >> > with new to_contacts relationship i have new error
>> >> > ArgumentError: Could not locate any relevant foreign key columns for
>> >> > primary
>> >> > join condition 'contact.id = :param_1' on relationship
>> >> > Contact.to_contacts.
>> >> > Ensure that referencing columns are associated with a ForeignKey or
>> >> > ForeignKeyConstraint, or are annotated in the join condition with the
>> >> > foreign() annotation.
>> >> >
>> >> > On Wed, Sep 24, 2014 at 5:49 AM, Michael Bayer
>> >> > <mike...@zzzcomputing.com>
>> >> > wrote:
>> >> >>
>> >> >> to_contacts = db.relationship('Contact',
>> >> >> secondary='contactrelation',
>> >> >> primaryjoin='id== ContactRelation.from_contact_id',
>> >> >> secondaryjoin='id== ContactRelation.to_contact_id',
>> >> >>
>> >> >> or
>> >> >>
>> >> >> to_contacts = db.relationship('Contact',
>> >> >> secondary=contactrelation,
>> >> >> primaryjoin=id== contactrelation.c.from_contact_id,
>> >> >> secondaryjoin=id== contactrelation.c.to_contact_id,
>> >> >>
>> >> >> see examples:
>> >> >>
>> >> >>
>> >> >>
>> >> >>
>> >> >> http://docs.sqlalchemy.org/en/rel_0_9/orm/relationships.html#self-referential-many-to-many-relationship
>> >> >>
>> >> >>
>> >> >>
>> >> >>
>> >> >> On Sep 23, 2014, at 5:26 PM, Mohammad Reza Kamalifard
>> >> >> <mr.kamalif...@gmail.com> wrote:
>> >> >>
>> >> >> Using contactrelation.from_contact_id ?
>> >> >> I have AttributeError: 'Table' object has no attribute
>> >> >> 'from_contact_id'
>> >> >> Error.
>> >> >>
>> >> >> On Tue, Sep 23, 2014 at 4:48 PM, Michael Bayer
>> >> >> <mike...@zzzcomputing.com>
>> >> >> wrote:
>> >> >> >
>> >> >> > table name, not class name, please see
>> >> >> >
>> >> >> >
>> >> >> > http://docs.sqlalchemy.org/en/rel_0_9/orm/extensions/declarative.html#declarative-many-to-many
>> >> >> >
>> >> >> >
>> >> >> > On Sep 23, 2014, at 8:33 AM, Mohammad Reza Kamalifard
>> >> >> > <mr.kamalif...@gmail.com> wrote:
>> >> >> >
>> >> >> > In my application with SQLAlchemy i need to create many to many
>> >> >> > relationship between two contact object also sotre data for each
>> >> >> > of
>> >> >> > relatioship here is my Contact model
>> >> >> >
>> >> >> > class Contact(db.Model):
>> >> >> > __tablename__ = 'contact'
>> >> >> > id = db.Column(db.Integer, primary_key=True)
>> >> >> > name = db.Column(db.Unicode(120), nullable=False,
>> >> >> > unique=False)
>> >> >> > user_id = db.Column(db.Integer, db.ForeignKey('user.id'))
>> >> >> >
>> >> >> > to_contacts = db.relationship('Contact',
>> >> >> > secondary='ContactRelation',
>> >> >> > primaryjoin='id==
>> >> >> > ContactRelation.from_contact_id',
>> >> >> > secondaryjoin='id==
>> >> >> > ContactRelation.to_contact_id',
>> >> >> >
>> >> >> > backref='from_contacts')
>> >> >> >
>> >> >> >
>> >> >> > and my association class ContactRelation:
>> >> >> >
>> >> >> > class ContactRelation(db.Model):
>> >> >> > __tablename__ = 'contactrelation'
>> >> >> > id = db.Column(db.Integer, primary_key=True)
>> >> >> > from_contact_id = db.Column(db.Integer,
>> >> >> > db.ForeignKey('contact.id'))
>> >> >> > to_contact_id = db.Column(db.Integer,
>> >> >> > db.ForeignKey('contact.id'))
>> >> >> > relation_type = db.Column(db.String(100), nullable=True)
>> >> >> >
>> >> >> > every thing seems good but i have error :
>> >> >> > AttributeError: type object 'ContactRelation' has no attribute 'c'
>> >> >> >
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