python - Avoid retrieving object to delete in many to many rel SQLAlchemy -

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is there way avoid retrieving object delete in many-to-many relationship?

assign = table('manytomany', base.metadata,     column('pid', string(...), foreignkey('parent.pid')),     column('cid', string(...), foreignkey('child.cid')) )  class parent():     ....     childs = relationship("child", secondary = assign, backref = 'parent')

i know can this:

obj = session.query(table).get(pk_id) session.delete(obj)

but have 1 database access, like:

session.query(table).filter_by(id = pk_id).delete()

i got error because of many-to-many rel:

'cannot delete or update parent row: foreign key constraint fails...'

is possible? thx lot

using session.query() retrieve object's data database first. avoid have use table object associated orm object directly.

session.execute(parent.__table__.delete().where(parent.id==pk_id))

this issue single delete sql statement database removing parent record. (parent.id synonym parent.__table__.c.id)

to resolve foreign key error have delete records in assign table first.

session.execute(assign.delete().where(assign.c.pid==pk_id))

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