How can i query different indexes with langchain in python

I’m making a question and answer application with python and langchain. I store each pdf in an index. After querying an index in Python code, I cannot query if I change the index I am on. How can I perform the index switch operation?

Can I ask why you’re storing each PDF in its own index? If the application needs access to all of the PDFs in question we suggest using a single index to store their data.

Multiple users will use the application and each will upload their own documents and ask questions to it. In such a case, should I use a single index? If I do that, how will I separate the user data in the index?

@halibrahimdogan For use cases like yours, we recommend using namespaces instead of multiple indexes. Queries and other data plane operations are limited to one namespace, so different requests can search different subsets of your index. In your case, it sounds like each user can be mapped to a distinct namespace.

An added benefit of using namespaces is resource management. You can immediately create a new namespace by upserting records to it, whereas creating a new index will take considerably longer. The same goes for deletion processes. Furthermore, namespaces introduce several cost-saving opportunities. For more details, please see Using namespaces instead of several indexes.

To learn more about interacting with namespaces via the LangChain integration, please see Setting up LangChain.