Limiting Relationship Depths

[Michael P. McDonnell]

Hey team - 

I was wondering - is it possible to limit the depth of objects by which SA will populate members?

Say I have a Person who is on a Team that plays a Game

class Person(Base):

  # .....

  team = relationship("Team", uselist=False)

class Team(Base):

  # .....

  game = relationship("Game", uselist=False)

 class Game(Base):

  # ....

If I get a person - I don't want it to go all the way down and grab the game object. Just the team one.

Is there a setting that makes that easy?

[Jonathan Vanasco]

This section of the narrative dogs will help you configure the relationship as you want.

   https://docs.sqlalchemy.org/en/13/orm/loading_relationships.html

In terms of API docs, 

     https://docs.sqlalchemy.org/en/13/orm/relationship_api.html

look for the `lazy` keyword

[Michael P. McDonnell]

Awesome, thank you Jonathan. 

I know I've read that at least 3-4 times, but I think I've been staring at the screen too much these days to actually read. I'll give it a go and let you know how it goes!

--
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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[Jonathan Vanasco]

On Wednesday, June 26, 2019 at 4:01:31 PM UTC-4, Michael P. McDonnell wrote:

Awesome, thank you Jonathan. 

I know I've read that at least 3-4 times, but I think I've been staring at the screen too much these days to actually read. I'll give it a go and let you know how it goes!

SqlAlchemy doesn't fetch the relationship by default.  You have to configure it to via 'lazy'; and tell it to fetch more things via dynamic loading options on the query.  

Staring at the docs a while is a good thing.  Very shortly it will make sense --  i promise!  And if you do things wrong, post your example here and we'll all help you figure it out.