The inconsistency of the number of documnets from retrievers

[dkbs12]

Hello,
I'm tying to make a Long Form QA model with both of BM25 retriever and Embedding retriever.
I set 5 for both 'top_k' of retriever, but I found the number of produced documents is 7.
I'm wondering why the number of documents is 7, not 10.
You can refer to the notebook on the github as below;

• Phase01_LFQA_test_08_01.ipynb

Thank you for your help.

[anakin87]

Hello...

The same relevant Document might be retrieved by the 2 different Retrievers.

In such a case, duplicate Documents are discarded in the JoinDocuments component.

See the API Reference.