How do metadata filters work with vector search?
PICTURE THIS: AN LLM TURN
Simple meaning
You restrict candidates by tenant, date, product, or ACL before or during ANN search.
WHY — Tokens instead of words?
LLMs use tokens (not full words) because it helps them:
question about Vector DB.
trade-offs, and what you would actually do on a GenAI / LLM project - not buzzwords.
Each piece maps to a number the network can learn.
Fixed pieces are what transformers expect as input.
STEPS — What happens with tokens?
Before the model can read a sentence, it goes through these steps:
- 1You restrict candidates by
tenant, date, product, or ACL before or during ANN search.
- 2Filters enforce security and
freshness that embeddings cannot.
- 3Poor filter design either
leaks data or returns empty results.
- 4Context mix
Attention looks at nearby tokens together.
- 5Next token
The model scores what should come next.
- 6Decode
IDs turn back into readable text.
EXAMPLE — See it in action
Let's see how a real sentence is tokenized (tokens may vary by model):
Note: Actual tokens and IDs depend on the tokenizer (e.g., GPT, Llama, etc.).
Key takeaway
You restrict candidates by tenant, date, product, or ACL before or during ANN search. Filters enforce security and freshness that embeddings cannot.