Hi, Allen!
You can use something like this (yeah, I know that it isn't
declarative in any way):
class Node(Base):
__tablename__ = 'node'
id = Column(Integer, primary_key=True)
parent_id = Column(ForeignKey('node.id'))
parent = relation("Node", remote_side=[id])
mp_path = Column(sqlamp.PathField())
mp_depth = Column(sqlamp.DepthField())
mp_tree_id = Column(sqlamp.TreeIdField())
Node.mp = sqlamp.MPManager(
Node.__table__,
pk_field='id',
parent_id_field='parent_id',
path_field_name='mp_path',
depth_field_name='mp_depth',
tree_id_field_name='mp_tree_id'
)
Node.__mapper__.extension.append(Node.mp.mapper_extension)
Note that you need to define mp_* colums. You doesn't need it if you
create MPManager *before* creating mapper.
On the other hand you can use this hack (but I wouldn't recomend it):
class Node(Base):
__tablename__ = 'node'
id = Column(Integer, primary_key=True)
parent_id = Column(ForeignKey('node.id'))
parent = relation("Node", remote_side=[id])
Node.mp = sqlamp.MPManager(
Node.__table__,
pk_field='id',
parent_id_field='parent_id'
)
Node.__mapper__.extension.append(Node.mp.mapper_extension)
Node.__mapper__._configure_properties()
allen.fowler:
> Werner,
>
> On Aug 7, 12:36 pm, werner <wbru...@free.fr> wrote:
> > Allen,
> >
> > allen.fowler wrote:
> >
> > > On Aug 6, 6:54 pm, AF <allen.fow...@yahoo.com> wrote:
> >
> > >> Hello all,
> >
> > >> Has anyone here used the "sqlamp: Materialized Path for SQLAlchemy"
> > >> library?
> >
> > >> I am wondering:
> >
> > >> 1) Does it seem to work well?
> >
> > >> 2) Did you use it with Declarative Base, and if so, how did you
> > >> configure it?
> >
> > > Anybody?
> >
> > > Specifically, I am wondering about how adapt the sample code at:
> >
> > >http://sqlamp.angri.ru/#quickstart
> >
> > > ... so that it works with declarative base.
> >
> > I haven't used this library and I am no SA expert so take the following
> > with a grain (or two) of salt.
> >
> > I would translate this:
> >
> > class Node(object):
> > mp = sqlamp.MPManager(
> > node_table, node_table.c.id, node_table.c.parent_id
> > )
> >
> > To:
> > class Node(Base):
> > __table__ = sa.Table(u'node', metadata,
> > sa.Column(u'id', sa.Integer(), sa.Sequence('gen_sample_id'),
> > primary_key=True, nullable=False),
> > sa.Column(u'parent_id', sa.Integer(), sa.ForeignKey(u'node.id')),
> > ...
> > )
> >
> > mp = sqlamp.MPManager(
> > __table__, __table__.c.id, __table__.c.parent_id)
> >
> > Werner
>
> Thank you...
>
> Though, that does not look at all like typical Declarative Base code
> I've seen / been using. Why the explicit assignment to __table__?
>
> Further, where does the "extension=[Node.mp.mapper_extension]" binding
> happen?
>
> Thank you again,
> AF
--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"sqlalchemy" group.
To post to this group, send email to sqlalchemy@googlegroups.com
To unsubscribe from this group, send email to
sqlalchemy+unsubscr...@googlegroups.com
For more options, visit this group at
http://groups.google.com/group/sqlalchemy?hl=en
-~----------~----~----~----~------~----~------~--~---
