Here are a few title options, each emphasizing a different aspect of the article: **Focus on Problem:** * **Can One Django Model Access Multiple Tables? Exploring Dynamic Table Mapping** * **Django

Dynamic Model Table Mapping in Django

This question explores the possibility of using a single Django model to interact with dynamic tables sharing a common schema.

Can a Single Model Draw Data from Multiple Tables?

No, a single Django model cannot draw data from multiple tables directly. Django operates on the principle of one model per table. However, there is a workaround for this limitation.

Dynamic Table Assignment

One approach is to create a factory function that returns a new model class with a dynamic db_table attribute:

<code class="python">def getModel(db_table):
  class MyClass(models.Model):
     # Define model fields as usual ...
     class Meta:
       db_table = db_table

  return MyClass</code>

This allows you to create new model classes on the fly, each with a specific db_table.

Metaclass for Run-Time Name Modification

However, this approach requires creating a new class instance each time the getModel function is called. To avoid this, a metaclass can be used to change the class name dynamically:

<code class="python">def getModel(db_table):
  class MyClassMetaclass(models.base.ModelBase):
    def __new__(cls, name, bases, attrs):
      name += db_table
      return models.base.ModelBase.__new__(cls, name, bases, attrs)

  class MyClass(models.Model):
    __metaclass__ = MyClassMetaclass

    class Meta:
      db_table = db_table

  return MyClass</code>

Dynamic Meta Attribute Assignment

Additionally, Django allows you to set the db_table attribute dynamically on an existing model class:

<code class="python">MyModel._meta.db_table = '10293847_table'
MyModel.objects.all()</code>

This provides another option for assigning tables to models at run-time.

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