On Fri, Jul 5, 2019, at 6:16 AM, Simon King wrote:
> In Python, modules are executed when they are imported. Class
> definitions are executable statements, where the metaclass is called
> to construct the *class*. When you import a module containing
> declarative classes, the SQLAlchemy metaclass is called for each of
> those classes, building the mappings, registering the polymorphic
> identities and so on.

> 
> Simon
> 
> On Fri, Jul 5, 2019 at 10:58 AM natsjoo sodillepa <[email protected]> wrote:
> >
> > For the curious. One thing that lingers around is the question: how does 
> > SQLalchemy make the connection between the parent and the child classes?
> >
> > In the separate modules, where the child classes are defined there is no 
> > other code. The only thing that gets executed is the class construction, 
> > but as
> > far as I know that doesn't trigger execution of code in the parent class. I 
> > know that SQLalchemy uses a metaclass but that's used only for
> > instantiation of instances, not of classes, or is it?
> >
> > --
> > SQLAlchemy -
> > The Python SQL Toolkit and Object Relational Mapper
> >
> > http://www.sqlalchemy.org/
> >
> > To post example code, please provide an MCVE: Minimal, Complete, and 
> > Verifiable Example. See http://stackoverflow.com/help/mcve for a full 
> > description.
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> -- 
> SQLAlchemy - 
> The Python SQL Toolkit and Object Relational Mapper
> 
> http://www.sqlalchemy.org/
> 
> To post example code, please provide an MCVE: Minimal, Complete, and 
> Verifiable Example. See http://stackoverflow.com/help/mcve for a full 
> description.
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-- 
SQLAlchemy - 
The Python SQL Toolkit and Object Relational Mapper

http://www.sqlalchemy.org/

To post example code, please provide an MCVE: Minimal, Complete, and Verifiable 
Example.  See  http://stackoverflow.com/help/mcve for a full description.
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