Flask-SQLAlchemy: How to conditionally insert or update a row

Question

My application uses a combination of Flask, Flask-SQLAlchemy, Flask-WTF and Jinja2.

In its current incarnation, I have a settings table. The table will only have one rec

Answer 1

Once your form is validated etc,

To add a new record:

new_provider = Provider(form.rssfeed.data)
db.session.add(new_provider)
db.session.commit()

To update an existing record:

existing_provider = Provider.query.get(1) # or whatever
# update the rssfeed column
existing_provider.rssfeed = form.rssfeed.data
db.session.commit()

The trick in updating is that you just have to change the particular field and do a commit. rest is taken care by the db session. I think you are using the merge function which is now deprecated in SQLAlchemy.