I am trying to make my web application work on offline mode by using pouchDB. but the backend database server i used is PostgreSQL (NoSQL). I couldn't find a way to Sync my PouchDB data to postgreSQL when my app came back to online. Can anyone please give me an idea how to do it
Short answer: You can't. It's impossible. Give up. You need CouchDB.
Long answer: You have two options:
See also this answer from another question.