verifier.org

ClickHouse

brute force so fast it sometimes beats an index

free self-hosted; cloud pricing not verified here#analytics-workloads-with#events#clickstream

the under-considered answer when your vectors live beside a lot of structured data you also want to aggregate — and the wrong answer for pure low-latency rag.

clickhouse added hnsw-based vector similarity indexes that became genuinely usable during 2025, but the more interesting property is its scan speed. with a selective filter reducing the candidate set, an exact brute-force scan in clickhouse can beat an approximate index elsewhere — and you get perfect recall rather than an approximation.

that makes it a strong fit for a specific shape of problem: semantic search over data you are also aggregating and filtering heavily, like logs, events or clickstream with embeddings attached.

the description above is ours, condensed from the ranking. pricing moves — check it on the vendor's own page before you rely on it.

pricing
free self-hosted; cloud pricing not verified here
our verdict

the under-considered answer when your vectors live beside a lot of structured data you also want to aggregate — and the wrong answer for pure low-latency rag.

we researched this category against vendors' own pricing pages and licence files. that is where this line comes from — not from the vendor, and not from anything they paid for.

more vector databases

Cloudflare Vectorize

vector index that runs on workers, beside cloudflare's own inference

#serverless#workers

Marqo

search engine that generates and stores its own embeddings for you

#embeddings-included

Upstash Vector

serverless vector database billed per request, with an http api

#serverless#http-api

pgvector

we checked thisfree — PostgreSQL License

the correct default for most teams, and it quietly got good

#almost-everyone-start-he#migrate-on-a-measured-th#not-a-vendor-s-table