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Python

Andras Andras
Andras Andras
8,230 Points
Posted by Andras Andras
Andras Andras
8,230 Points

Python, SQLAlchemy cascade - save-update

Hi there,

I would like to ask if it is possible to update the Child records automatically when Parent is changing in a one-to-many relationship.

For example; I have a task list for every project at the company:

Project 1 (Parent table)

-> Project 1 - Task1 (Child table) 
-> Project 1 - Task2 
-> Project 1 - Task3 

Project2

-> Project 2 - Task1
-> Project 2 - Task2
-> Project 2 - Task3

I want to change the project name from "Project 1" to "Project First" in the Parent table. How can I achieve to update the name of the project in the Child table as well?

1 Answer

Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

You used the term in your title .. what you want is a cascade update. But I think you will need to enable that directly in the database engine you are using, if it supports it. And it most likely needs to be established at the same time the foreign key is. Check the documentation for your database.