question about the "examples/database_examples/chromadb_example.py" script

[jonathan2951]

Hi,
I have several newby questions about running cognee with a vector database.

1. I have Chromadb running locally on 8000 and my .env file looks looks this:

VECTOR_DB_PROVIDER=chromadb
VECTOR_DB_URL=http://localhost:8000
VECTOR_DB_PORT=8000
VECTOR_DB_KEY=""

I think this is redundant since the script sets the config:

    # Configure ChromaDB as the vector database provider
    cognee.config.set_vector_db_config(
        {
            "vector_db_url": "http://localhost:8000",  # Default ChromaDB server URL
            "vector_db_key": "",  # ChromaDB doesn't require an API key by default
            "vector_db_provider": "chromadb",  # Specify ChromaDB as provider
        }
    )

However when I run the script, I got an error about LanceDB:

 File "/Users/jonathan/Documents/WORK/cognee_chromadb/.venv/lib/python3.12/site-packages/lancedb/__init__.py", line 190, in connect_async
    await lancedb_connect(
RuntimeError: lance error: LanceError(IO): Operation not supported: Unsupported URI scheme: http in url http://localhost:8000/, /Users/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/lance-io-0.19.2/src/object_store.rs:936:27

Is my setup wrong ?

2. My second question is more general. The script creates a graph from a given document.
   If I want to create another graph with docs not related at all with this one, the pruning will wipe the existing collections:

# Clean any existing data (optional)
await cognee.prune.prune_data()
await cognee.prune.prune_system(metadata=True)

• does these 2 lines are required (or preferred) ?
• is there a way to specify a given collection where to save the graph data

Thank you advance,
jonathan

---

python: 3.12
chromadb: 1.3.4
cognee: chromadb:0.1.34