external knowledge retrival empty because of document table is empty

[dajianguo]

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Dify version

0.9.1

Cloud or Self Hosted

Self Hosted (Source)

Steps to reproduce

I use a external knowledge,but in the chatflow, but don't retrival anything.
Because of the document table is empty when use the external data

set.

✔️ Expected Behavior

knowledge can retrival results

❌ Actual Behavior

knowledge retrival empty

[dosubot]

Hey @dajianguo! 👋 I'm here to help you with any bugs, questions, or contributions you have for Dify. Let's squash those bugs together!

The issue you're experiencing with external knowledge retrieval being empty when the document table is empty in the self-hosted Dify version 0.9.1 is due to how the _fetch_dataset_retriever method operates. This method relies on the presence of documents in the Document table to determine available datasets. It uses a subquery to count the number of available documents for each dataset, and only datasets with a non-zero document count are considered for retrieval. If the document table is empty, the subquery will not find any datasets with available documents, resulting in an empty retrieval result ^[1].

To resolve this, ensure that there are documents in the Document table or adjust the logic to handle cases where the document table might be empty but external datasets should still be considered.

To continue talking to Dosu, mention @dosu.

[dajianguo]

Sorry I think it has been resovled in #9241 ; please close this question.

[sepa85]

Not sure if the same problem, but with cloud version 0.9.2 I also have empty result even if the knowledge test retrieves results.