How to upsert a pdf file in particular collection and then retrieving answers specifically from it

[avst65t]

I made a web app where users upload a pdf file. I want the app such that when user A uploads a file, it should be stored in collection A and when users asks questions it should answer from collection A specifically. There would be N number of users. The question answering should not be mixed up and answers should be from the collection of that users only. Please help ASAP. I'm in an emergency situation @HenryHengZJ.

Frontend: Next.js
Backend: FastAPI
QA: Flowise AI
Database(relational and vector): PostgreSQL

[avst65t]

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