replace/delete field using sqlalchemy

Question

Two part question. Using postgres in python. 1) How do I replace all fields from the same column that match a specified value? For example, let's say I want to replace any fields that match "green" with "red" in the "Color" column.

2) How to delete all fields from the same column that match a specified value? For example, I'm trying to deleted all fields that match "green" in the Color column.

Answer 1

Ad1. You need something like this:

session.query(Foo).filter_by(color = 'green').update({ 'color': 'red' })
session.commit()

Ad2. Similarly:

session.query(Foo).filter_by(color = 'green').delete()
session.commit()

You can find the querying documentation here and here.