I am new to Flask app development, i need some clarifications on using database with flask app. 
We have a MySQL db which has some metrics, currently we generate some reports using python using MySQL.connector.
We have python modules/functions to fetch the data from the db using mysql.connector and populate a dictionary which has data to be put in the report. 
My question is can i use the same python module in the app.py (if this is where i create the app) and get the data as dictionary and pass it to some template html to render the report?
If i can do this, what is the advantage of using Flask-MySql or Flask-SqlAlchemy and doing the app.config[] things which are mentioned in many tutorials?
I am trying to understand what should be used when.
well for ur case if ur have not much experience in sql i prefer u to use orm like Sqlalchemy. for flask there is an extension call flask-sqlalchemy.it uses python like syntax without using direct sql it is very easy to learn and well documented.but not recommended for advanced user cases.If u want to pass pure sql queries through flask and to have more capablities in database site better to use flask extension for mysql flask-mysql.It depend on ur requirement,capability and user case.
what is the Difference between using mysql connector and Flask-Mysql in Flask app?