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

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 columnexisting_provider.rssfeed = form.rssfeed.datadb.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.

I have managed to solve the problem doing these changes to the view.py file:

@app.route('/settings', methods=["GET","POST"])def settings():    """ show settings """    provider = Provider.query.get(1)    form = SettingsForm(request.form,obj=provider)    if request.method == "POST" and form.validate():        if provider:            provider.rssfeed = form.rssfeed.data            db.session.merge(provider)            db.session.commit()            flash("Settings changed")            return redirect(url_for("index"))        else:            provider = Provider(form.rssfeed.data)            db.session.add(provider)            db.session.commit()            flash("Settings added")            return redirect(url_for("index"))    return render_template("settings.html", form=form)