Well, I want to build a large-scale project, but I do not know which ORDBMS to choose. The app should handle real-time operations, not chatting, but things like future scheduling or reminders. It should be also really secure, fast and easy to use. And last but not least, should I use them both. I mean PostgreSQL with Python / Django and MongoDB with Node.js? Or would it be better to use PostgreSQL with Node.js?
*The project is going to use React for the front-end and GraphQL is going to be used for the API.
Thank you all. Any answer or advice would be really helpful!
I'd recommend using PostgreSQL and the built in row level security it offers. You can easily make multi-tenant real-time systems using it and https://www.graphile.org/postgraphile/ which gives you an GraphQL api guaranteed to be in sync with your database for free. Also, the transactional support in postgres shines in comparison to mongodb.