ChromaDB
Easiest-to-install open-source vector DB. `pip install chromadb` and you have a working DB in 2 lines of code. Perfect for first RAG projects.
Strengths
- Two-line install, `pip install chromadb`
- Pythonic Python API, no SQL to learn
- Open-source, self-hostable, no limited free quota
Limitations
- The index must fit in RAM: Chroma's documentation estimates about 245,000 embeddings of 1024 dimensions per GB of RAM, and every query slows down as the collection grows
- Fewer features than pgvector when you want SQL + vectors in the same query
Best for
- First RAG, pedagogical exercise, prototype
- Solo or desktop app that doesn't need a dedicated server