In sqlalchemy, how can I use polymorphic joined table inheritance when the child table has multiple foreign keys to the parent table?

I have a parent table called pbx_point that has a point_type column. I also have a child table called pbx_route, with a column called point_id pointing back to pbx_point.

I'd like to use sqlalchemy's joined table inheritance to relate these two tables via declarative base, and use polymorphic inheritance

This works fine - or rather, it would, if not for the following additional constraint: pbx_point also has a foreign key called initial_route_id pointing to pbx_route.

I'm also using reflection below, but the db is as I describ

Related to : In sqlalchemy, how can I use polymorphic joined table inheritance when the child table has multiple foreign keys to the parent table?
Join query from table with multiple foreign keys to same table primary key

I have a workorder system using SQL Express 2008. I have a table called Workorders that has several personnel that are linked to it via UserID. In the Workorder table I have TechID for the Technician, CustomerID for the Customer, QAID for quality assurance. These are linked back to the User Table via UserID (User Table PK). I want to join the tables to return Technician Name, Customer Name, and QA Name from the User Table and other job information information from the Workorder Table. I have no idea how to construct the join.

How do I create a child class from a parent class in SQLAlchemy's Joined Table Inheritance?

I'm developing a small database where there are far more People than Users, so currently have the following Model.

class Person(db.Model):
__tablename__ = 'people'
id = db.Column(db.Integer, primary_key = True)
forename = db.Column(db.String(64))
surname = db.Column(db.String(64))
memberships = db.relationship('Membership', backref='person')
def name(self):
return self.forename + ' ' + self.surname
def __repr__(self):
return '<Person %r %r>' % (self.forename, self.surname)
class User(Person):
__tablename__ = 'users'
How foreign key in a child table, can automatically get the value it actually has in the parent table

Can anybody tell whether a foreign key in a child table, can automatically get the value it actually has in the parent table?
I has two tables student and course table.Student SSC is foreign key in course.I am inserting data correctly into student table.But It gives me an error when I insert data into course table?Any suggestions?
Values of variables are got via post method of form.

$query1=mysql_query("INSERT INTO course VALUES(','$subject','$total','$attendce','$ssn')")or die(mysql_error());

This is error I am getting....

Cannot add or update a child row: a foreign key constraint fails

SQLAlchemy, filtering joined queries with table inheritance

First off, sorry if it turns out that what I'm trying to do is smoke crack here, I'm by no means a DB or SQLA expert. =)

I have two classes, Person and Organization, that use table inheritance to inherit from Contact. ( is an fkey to ), which is working fine.

I want to search from a search box and get a list of all contacts. Normally, when I'm after a set of things, I do this:

def build_query(self):
  return self.session.query(Person)
def filter_query(self, query)
    if self.search_form_values.get('name_last',None):
        query = query.filter(
SQLAlchemy: Multiple foreign keys to same table with compound primary key

In SQLAlchemy, imagine we have a table Foo with a compound primary key, and Bar, which has two foreign key constrains linking it to Foo (each Bar has two Foo objects).

My problem is with the relationship function, which makes me repeat the information (in the primaryjoin) which I have already given in the ForeightKeyConstraint (violating DRY). Is there some other way of structuring this so that I don't have to repeat information? Some way of passing the relevant ForeignKeyConstraint to relationship?

class Foo(Base):
sqlite: No such table found(parent table) error while creating foreign key in child table

I have created one Member_Master table whose primary key is member_id in sqlite manager for android and creating foreign key in child table e.g Event_Master for member_id from Member_Master. I was getting no such table found:Member_Master error
But now I am getting the following error :

SQLiteManager: CREATE TABLE "main"."Events_Master" ("event_id" NUMERIC PRIMARY KEY NOT
NULL ,"event_name" TEXT NOT NULL ,"event_details" TEXT NOT NULL ,"event_start_date"
,"event_venue" TEXT NOT NULL ,"min_level" NUMERIC,"status_id" NUMERIC,"member_id"
Database Table Relationships having foreing keys in both child and parent table

Let's say we have two tables CUSTOMER and VEHICLE having one to many relationships. VEHICLE has a CUSTOMERID as a foreign key in it which makes it a child table. The question is, Why i cannot have VEHICLEID as a foreign key into CUSTOMER table. I know it is not correct way, but i need to know the more detailed and in depth reason why it is not correct

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