We are working on a project where we have a running Milvus standalone with approximately 70M data inserted.

However, we encountered some issue regarding the delete operation. We attempted to delete entities based on this code linked here: https://github.com/milvus-io/pymilvus/blob/131989ac95587ce4664109ba9a2e2323cea42f33/pymilvus/orm/collection.py#L522.

Looks like the call to delete function was successful, but the entities were not deleted, so total entity number remained still the same, and collection was loaded with MMAP enabled. Why did the delete call have no effect and what is supposed to be the correct way to delete entities from collection?

We also have another problem when inserting into existed collection. In the project there will be daily new data inserted into the collection, so do we need to call create_index every time new data is inserted and load again, or will Milvus build the index for new data automatically given the collection has MMAP enabled? Also, do we need to release the collection to build index for new data?

Thanks in advance!