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SQLAlchemy (Flask) count model instances by unique values

One comes to a task that has to do with counting items in a database. We will describe the right approach here. Despite being so obvious I did not find much of the docs for junior developers to watch and learn. Here is a sample task and solution: Let's assume we have a model like so: class Cycle (db.Model): id = db.Column(db.Integer, primary_key= True ) object_id = db.Column(db.String, nullable= False ) Sample date populated into it will be: { id : 1 , object_id: 'unique1' }, { id : 2 , object_id: 'unique1' }, { id : 3 , object_id: 'unique2' }, { id : 4 , object_id: 'unique2' }, { id : 5 , object_id: 'unique2' }, { id : 6 , object_id: 'unique3' } We need to count unique model instances with same  object_id . To achieve this relatively simple task one would go straightforward. E.g. Fetch all the Cycle instances with a simple query and then...

Run Flask with Debug in PyCharm

I have gotten to setting UP a Flask environment for a project recently. Was completely puzzled by how to run this. I have used to running Django project with python manage.py script. This means pointing out a PyCharm interpreter into a certain point of entry, that is also a .py file also. In flask way of starting things there is another approach however. Here it is in Flask Docs. It states to set a variable FLASK_APP and then run a flask run command. This will confuse running a python script way of a project being run. Thus to fix this one needs to set a path to flask binary file. It usually is within a virtual environment binary directory, place where your python interpreter resides. So to set debugging one needs to set path to script binary one needs: Script: /path/to/env/bin/flask Script parameters: run   Environment variable  FLASK_APP=app.py Environment variable FLASK_DEBUG=True Set working directory back to your app path (It changes automatically according t...