fulltext search not work with milvus

[NiuBlibing]

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Dify version

0.11.0

Cloud or Self Hosted

Self Hosted (Docker)

Steps to reproduce

1. deploy dify with milvus
2. create knowledge, select Full-Text Search or Hybrid Search.
3. test recall with Full-Text Search

✔️ Expected Behavior

hit results

❌ Actual Behavior

nothing is recalled.

[dosubot[bot]]

The issue you're experiencing with full-text search not working with Milvus in Dify version 0.11.0 is due to the fact that Milvus does not support BM25 search. The search_by_full_text method in the MilvusVector class explicitly returns an empty list, indicating that full-text search functionality is not supported in this implementation ^[1].

If you need full-text search capabilities, consider using a different vector database that supports this feature.

To continue talking to Dosu, mention @dosu.

[NiuBlibing]

@crazywoola is there a plan to support BM25 for milvus? https://milvus.io/docs/embed-with-bm25.md#BM25