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Alex Spinov
Alex Spinov

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LanceDB Has a Free API: The Serverless Vector Database Built on Lance Format

Pinecone costs $70/month for 1M vectors. LanceDB stores them on disk for free. Embedded, serverless, and built for AI.

What Is LanceDB?

LanceDB is an open-source vector database built on the Lance columnar format. It's embedded (like SQLite) — no server, no Docker, no infrastructure.

import lancedb
import numpy as np

# Open database (creates directory if needed)
db = lancedb.connect("./my-lancedb")

# Create a table with vectors
data = [
    {"text": "The cat sat on the mat", "vector": np.random.rand(384).tolist()},
    {"text": "Dogs are great pets", "vector": np.random.rand(384).tolist()},
    {"text": "Machine learning is fun", "vector": np.random.rand(384).tolist()},
]
table = db.create_table("documents", data)

# Search
query_vector = np.random.rand(384).tolist()
results = table.search(query_vector).limit(5).to_pandas()
print(results[["text", "_distance"]])
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With Embeddings (Auto-Generate Vectors)

from lancedb.embeddings import get_registry
from lancedb.pydantic import LanceModel, Vector

# Use sentence-transformers for embeddings
embedder = get_registry().get("sentence-transformers").create()

class Document(LanceModel):
    text: str = embedder.SourceField()
    vector: Vector(embedder.ndims()) = embedder.VectorField()

# Vectors are generated automatically!
table = db.create_table("docs", schema=Document)
table.add([
    {"text": "The cat sat on the mat"},
    {"text": "Machine learning is transforming industries"},
    {"text": "Python is a great programming language"},
])

# Search with text (auto-embedded)
results = table.search("artificial intelligence").limit(3).to_pandas()
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Full-Text Search + Vector Search

# Hybrid search
results = (table
    .search("machine learning", query_type="hybrid")
    .limit(10)
    .to_pandas()
)
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Why LanceDB

Feature Pinecone LanceDB
Hosting Managed ($70+/mo) Embedded (free)
Setup Account, API key pip install lancedb
Storage Cloud only Local disk, S3, GCS
Full-text search No Yes
SQL queries No Yes
Versioning No Built-in (Lance format)
  • Zero infrastructure — no server to run, like SQLite for vectors
  • Disk-based — handle billions of vectors without $1000s in RAM
  • Multi-modal — store images, text, video alongside vectors
  • Versioning — Lance format supports time-travel queries
pip install lancedb
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Building AI search? Check out my AI tools or email spinov001@gmail.com.

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