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lancedb/docs/web-tests/py/test_search.py
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Jack Ye b21fb2a4dc docs: bring the open-source documentation into this repository
The pages describing this code lived in lancedb/docs, a repository with ten
stars that neither contributing guide mentioned. A user who hit a wrong page
while reading the source had to find a separate, near-invisible repository to
fix it. These 102 pages now sit beside the code, and a documentation fix is a
pull request in the repository the reader already had open.

`docs/web` is a complete Mintlify site: `cd docs/web && mint dev` serves it with
no other checkout. Enterprise pages stay private and are merged in when the
published site is assembled, so links into them do not resolve here — every
open-source page does.

`docs/web-tests` holds the tests the code examples are extracted from. They ran
against a published wheel before; here they can run against this repository's
own SDK, so an example that stops compiling fails the pull request that broke
it rather than being noticed later.

Both directories sit beside `docs/src` and are invisible to it: mkdocs reads
`docs_dir: src`, so the SDK reference builds and deploys exactly as before.
2026-09-02 21:09:30 -07:00

731 lines
24 KiB
Python

# SPDX-License-Identifier: Apache-2.0
# SPDX-FileCopyrightText: Copyright The LanceDB Authors
# --8<-- [start:import-lancedb]
import lancedb
# --8<-- [end:import-lancedb]
# --8<-- [start:import-numpy]
from lancedb.query import BoostQuery, MatchQuery
import numpy as np
import pyarrow as pa
# --8<-- [end:import-numpy]
# --8<-- [start:import-datetime]
from datetime import datetime
# --8<-- [end:import-datetime]
# --8<-- [start:import-lancedb-pydantic]
from lancedb.pydantic import Vector, LanceModel
# --8<-- [end:import-lancedb-pydantic]
# --8<-- [start:import-pydantic-base-model]
from pydantic import BaseModel
# --8<-- [end:import-pydantic-base-model]
# --8<-- [start:import-lancedb-fts]
from lancedb.index import FTS
# --8<-- [end:import-lancedb-fts]
# --8<-- [start:import-os]
import os
# --8<-- [end:import-os]
# --8<-- [start:import-embeddings]
from lancedb.embeddings import get_registry
# --8<-- [end:import-embeddings]
import pytest
# --8<-- [start:class-definition]
class Metadata(BaseModel):
source: str
timestamp: datetime
class Document(BaseModel):
content: str
meta: Metadata
class LanceSchema(LanceModel):
id: str
vector: Vector(1536)
payload: Document
# --8<-- [end:class-definition]
def test_vector_search():
# --8<-- [start:exhaustive_search]
uri = "data/sample-lancedb"
db = lancedb.connect(uri)
data = [
{"vector": row, "item": f"item {i}"}
for i, row in enumerate(np.random.random((10_000, 1536)).astype("float32"))
]
tbl = db.create_table("vector_search", data=data, mode="overwrite")
tbl.search(np.random.random((1536))).limit(10).to_list()
# --8<-- [end:exhaustive_search]
# --8<-- [start:exhaustive_search_cosine]
tbl.search(np.random.random((1536))).distance_type("cosine").limit(10).to_list()
# --8<-- [end:exhaustive_search_cosine]
# --8<-- [start:create_table_with_nested_schema]
# Let's add 100 sample rows to our dataset
data = [
LanceSchema(
id=f"id{i}",
vector=np.random.randn(1536),
payload=Document(
content=f"document{i}",
meta=Metadata(source=f"source{i % 10}", timestamp=datetime.now()),
),
)
for i in range(100)
]
# Synchronous client
tbl = db.create_table("documents", data=data, mode="overwrite")
# --8<-- [end:create_table_with_nested_schema]
# --8<-- [start:search_result_as_pyarrow]
tbl.search(np.random.randn(1536)).to_arrow()
# --8<-- [end:search_result_as_pyarrow]
# --8<-- [start:search_result_as_pandas]
tbl.search(np.random.randn(1536)).to_pandas()
# --8<-- [end:search_result_as_pandas]
# --8<-- [start:search_result_as_pandas_flatten_true]
tbl.search(np.random.randn(1536)).to_pandas(flatten=True)
# --8<-- [end:search_result_as_pandas_flatten_true]
# --8<-- [start:search_result_as_pandas_flatten_1]
tbl.search(np.random.randn(1536)).to_pandas(flatten=1)
# --8<-- [end:search_result_as_pandas_flatten_1]
# --8<-- [start:search_result_as_list]
tbl.search(np.random.randn(1536)).to_list()
# --8<-- [end:search_result_as_list]
# --8<-- [start:search_result_as_pydantic]
tbl.search(np.random.randn(1536)).to_pydantic(LanceSchema)
# --8<-- [end:search_result_as_pydantic]
@pytest.mark.asyncio
async def test_vector_search_async():
# --8<-- [start:exhaustive_search_async]
uri = "data/sample-lancedb"
async_db = await lancedb.connect_async(uri)
data = [
{"vector": row, "item": f"item {i}"}
for i, row in enumerate(np.random.random((10_000, 1536)).astype("float32"))
]
async_tbl = await async_db.create_table(
"vector_search_async", data=data, mode="overwrite"
)
(await (await async_tbl.search(np.random.random((1536)))).limit(10).to_list())
# --8<-- [end:exhaustive_search_async]
# --8<-- [start:exhaustive_search_async_cosine]
(
await (await async_tbl.search(np.random.random((1536))))
.distance_type("cosine")
.limit(10)
.to_list()
)
# --8<-- [end:exhaustive_search_async_cosine]
# --8<-- [start:create_table_async_with_nested_schema]
# Let's add 100 sample rows to our dataset
data = [
LanceSchema(
id=f"id{i}",
vector=np.random.randn(1536),
payload=Document(
content=f"document{i}",
meta=Metadata(source=f"source{i % 10}", timestamp=datetime.now()),
),
)
for i in range(100)
]
async_tbl = await async_db.create_table(
"documents_async", data=data, mode="overwrite"
)
# --8<-- [end:create_table_async_with_nested_schema]
# --8<-- [start:search_result_async_as_pyarrow]
await (await async_tbl.search(np.random.randn(1536))).to_arrow()
# --8<-- [end:search_result_async_as_pyarrow]
# --8<-- [start:search_result_async_as_pandas]
await (await async_tbl.search(np.random.randn(1536))).to_pandas()
# --8<-- [end:search_result_async_as_pandas]
# --8<-- [start:search_result_async_as_list]
await (await async_tbl.search(np.random.randn(1536))).to_list()
# --8<-- [end:search_result_async_as_list]
def test_fts_fuzzy_query():
uri = "data/fuzzy-example"
db = lancedb.connect(uri)
table = db.create_table(
"my_table_fts_fuzzy",
data=pa.table(
{
"text": [
"fa",
"fo", # spellchecker:disable-line
"fob",
"focus",
"foo",
"food",
"foul",
]
}
),
mode="overwrite",
)
table.create_fts_index("text", replace=True)
results = table.search(MatchQuery("foo", "text", fuzziness=1)).to_pandas()
assert len(results) == 4
assert set(results["text"].to_list()) == {
"foo",
"fo", # 1 deletion # spellchecker:disable-line
"fob", # 1 substitution
"food", # 1 insertion
}
def test_fts_boost_query():
uri = "data/boost-example"
db = lancedb.connect(uri)
table = db.create_table(
"my_table_fts_boost",
data=pa.table(
{
"title": [
"The Hidden Gems of Travel",
"Exploring Nature's Wonders",
"Cultural Treasures Unveiled",
"The Nightlife Chronicles",
"Scenic Escapes and Challenges",
],
"desc": [
"A vibrant city with occasional traffic jams.",
"Beautiful landscapes but overpriced tourist spots.",
"Rich cultural heritage but humid summers.",
"Bustling nightlife but noisy streets.",
"Scenic views but limited public transport options.",
],
}
),
mode="overwrite",
)
table.create_fts_index("desc", replace=True)
results = table.search(
BoostQuery(
MatchQuery("beautiful, cultural, nightlife", "desc"),
MatchQuery("bad traffic jams, overpriced", "desc"),
),
).to_pandas()
# we will hit 3 results because the positive query has 3 hits
assert len(results) == 3
# the one containing "overpriced" will be negatively boosted,
# so it will be the last one
assert (
results["desc"].to_list()[2]
== "Beautiful landscapes but overpriced tourist spots."
)
def test_fts_native():
# --8<-- [start:basic_fts]
uri = "data/sample-lancedb"
db = lancedb.connect(uri)
table = db.create_table(
"my_table_fts",
data=[
{"vector": [3.1, 4.1], "text": "Frodo was a happy puppy"},
{"vector": [5.9, 26.5], "text": "There are several kittens playing"},
],
mode="overwrite",
)
table.create_fts_index("text")
table.search("puppy").limit(10).select(["text"]).to_list()
# [{'text': 'Frodo was a happy puppy', '_score': 0.6931471824645996}]
# ...
# --8<-- [end:basic_fts]
# --8<-- [start:fts_config_stem]
table.create_fts_index("text", tokenizer_name="en_stem", replace=True)
# --8<-- [end:fts_config_stem]
# --8<-- [start:fts_config_folding]
table.create_fts_index(
"text",
language="French",
stem=True,
ascii_folding=True,
replace=True,
)
# --8<-- [end:fts_config_folding]
# --8<-- [start:fts_prefiltering]
table.search("puppy").limit(10).where("text='foo'", prefilter=True).to_list()
# --8<-- [end:fts_prefiltering]
# --8<-- [start:fts_postfiltering]
table.search("puppy").limit(10).where("text='foo'", prefilter=False).to_list()
# --8<-- [end:fts_postfiltering]
# --8<-- [start:fts_with_position]
table.create_fts_index("text", with_position=True, replace=True)
# --8<-- [end:fts_with_position]
# --8<-- [start:fts_incremental_index]
table.add([{"vector": [3.1, 4.1], "text": "Frodo was a happy puppy"}])
table.optimize()
# --8<-- [end:fts_incremental_index]
@pytest.mark.asyncio
async def test_fts_native_async():
# --8<-- [start:basic_fts_async]
uri = "data/sample-lancedb"
async_db = await lancedb.connect_async(uri)
async_tbl = await async_db.create_table(
"my_table_fts_async",
data=[
{"vector": [3.1, 4.1], "text": "Frodo was a happy puppy"},
{"vector": [5.9, 26.5], "text": "There are several kittens playing"},
],
mode="overwrite",
)
# async API uses our native FTS algorithm
await async_tbl.create_index("text", config=FTS())
await (await async_tbl.search("puppy")).select(["text"]).limit(10).to_list()
# [{'text': 'Frodo was a happy puppy', '_score': 0.6931471824645996}]
# ...
# --8<-- [end:basic_fts_async]
# --8<-- [start:fts_config_stem_async]
await async_tbl.create_index(
"text", config=FTS(language="English", stem=True, remove_stop_words=True)
)
# --8<-- [end:fts_config_stem_async]
# --8<-- [start:fts_config_folding_async]
await async_tbl.create_index(
"text", config=FTS(language="French", stem=True, ascii_folding=True)
)
# --8<-- [end:fts_config_folding_async]
# --8<-- [start:fts_prefiltering_async]
await (await async_tbl.search("puppy")).limit(10).where("text='foo'").to_list()
# --8<-- [end:fts_prefiltering_async]
# --8<-- [start:fts_postfiltering_async]
await (
(await async_tbl.search("puppy"))
.limit(10)
.where("text='foo'")
.postfilter()
.to_list()
)
# --8<-- [end:fts_postfiltering_async]
# --8<-- [start:fts_with_position_async]
await async_tbl.create_index("text", config=FTS(with_position=True))
# --8<-- [end:fts_with_position_async]
# --8<-- [start:fts_incremental_index_async]
await async_tbl.add([{"vector": [3.1, 4.1], "text": "Frodo was a happy puppy"}])
await async_tbl.optimize()
# --8<-- [end:fts_incremental_index_async]
def _vectors(n, dim, seed=0, column="vector"):
rng = np.random.default_rng(seed)
return [
{column: rng.random(dim).astype("float32"), "id": i} for i in range(n)
]
def _build_indexed_table(db, name, dim=128, n=512):
tbl = db.create_table(name, _vectors(n, dim), mode="overwrite")
tbl.create_index(metric="cosine", num_partitions=4, num_sub_vectors=8)
return tbl
def test_vs_distance_metric_and_brute_force(tmp_db):
tbl = tmp_db.create_table("vs_metric", _vectors(64, 1536), mode="overwrite")
# --8<-- [start:configure_distance_metric]
tbl.search(np.random.random((1536))).distance_type("cosine").limit(10).to_list()
# --8<-- [end:configure_distance_metric]
# --8<-- [start:brute_force_search]
tbl.search(np.random.random((1536))).limit(3).to_list()
# --8<-- [end:brute_force_search]
def test_vs_select_vector_column(tmp_db):
db = tmp_db
# --8<-- [start:select_vector_column]
import pyarrow as pa
schema = pa.schema([
pa.field("id", pa.int32()),
pa.field(
"image",
pa.struct([pa.field("embedding", pa.list_(pa.float32(), 2))]),
),
])
table = db.create_table(
"nested",
data=[{"id": 0, "image": {"embedding": [0.0, 1.0]}}],
schema=schema,
)
# Inferred: the only vector leaf is `image.embedding`.
table.search([0.0, 1.0]).limit(1).to_list()
# Explicit: required when more than one vector column matches.
table.search([0.0, 1.0], vector_column_name="image.embedding").limit(1).to_list()
# --8<-- [end:select_vector_column]
def test_vs_index_nested_column(tmp_db):
dim = 16
schema = pa.schema(
[
pa.field("id", pa.int32()),
pa.field(
"image",
pa.struct([pa.field("embedding", pa.list_(pa.float32(), dim))]),
),
]
)
rng = np.random.default_rng(0)
data = [
{"id": i, "image": {"embedding": rng.random(dim).astype("float32").tolist()}}
for i in range(512)
]
table = tmp_db.create_table(
"nested_index", data=data, schema=schema, mode="overwrite"
)
# --8<-- [start:index_nested_column]
table.create_index(vector_column_name="image.embedding")
# --8<-- [end:index_nested_column]
assert table.list_indices()
def test_vs_indexed_queries(tmp_db):
table = _build_indexed_table(tmp_db, "vs_indexed", dim=128, n=512)
embedding = np.random.random(128)
# --8<-- [start:exact_vs_approximate_distances]
# Indexed ANN search without refinement (fast, approximate `_distance`)
fast_results = (
table.search(embedding)
.limit(10)
.to_pandas()
)
# Recompute distances on full vectors for reranked candidates
exact_distance_results = (
table.search(embedding)
.limit(10)
.refine_factor(1)
.to_pandas()
)
# Rerank a larger candidate set for better recall (higher latency)
higher_recall_results = (
table.search(embedding)
.limit(10)
.refine_factor(20)
.to_pandas()
)
# --8<-- [end:exact_vs_approximate_distances]
# --8<-- [start:bypass_vector_index]
table.search(embedding).bypass_vector_index().limit(5).to_pandas()
# --8<-- [end:bypass_vector_index]
assert len(fast_results) == 10
assert len(exact_distance_results) == 10
assert len(higher_recall_results) == 10
def test_vs_fast_search(tmp_db, monkeypatch):
table = _build_indexed_table(tmp_db, "vs_fast", dim=128, n=512)
embedding = np.random.random(128)
# `fast_search` is an Enterprise/async query flag; strip it so the snippet
# runs against a local OSS table without changing what readers see.
real_search = table.search
monkeypatch.setattr(
table,
"search",
lambda *a, **k: real_search(
*a, **{key: val for key, val in k.items() if key != "fast_search"}
),
)
# --8<-- [start:fast_search]
table.search(embedding, fast_search=True).limit(5).to_pandas()
# --8<-- [end:fast_search]
def test_vs_distance_range(tmp_db):
tbl = tmp_db.create_table("vs_distance_range", _vectors(256, 256), mode="overwrite")
# --8<-- [start:search_distance_range]
query = np.random.random(256)
# Search for the vectors within the range of [0.1, 0.5)
tbl.search(query).distance_range(0.1, 0.5).to_arrow()
# Search for the vectors with the distance less than 0.5
tbl.search(query).distance_range(upper_bound=0.5).to_arrow()
# Search for the vectors with the distance greater or equal to 0.1
tbl.search(query).distance_range(lower_bound=0.1).to_arrow()
# --8<-- [end:search_distance_range]
def test_vs_multivector_search(tmp_db):
schema = pa.schema(
[
pa.field("id", pa.int64()),
pa.field("vector", pa.list_(pa.list_(pa.float32(), 256))),
]
)
rng = np.random.default_rng(0)
data = [{"id": i, "vector": rng.random(size=(2, 256)).tolist()} for i in range(64)]
tbl = tmp_db.create_table(
"vs_multivector", data=data, schema=schema, mode="overwrite"
)
# --8<-- [start:multivector_search]
query_multi = np.random.random(size=(2, 256))
results_multi = tbl.search(query_multi).limit(5).to_pandas()
# --8<-- [end:multivector_search]
assert len(results_multi) <= 5
def test_vs_binary_search(tmp_db):
db = tmp_db
# --8<-- [start:search_binary_vectors]
import numpy as np
import pyarrow as pa
schema = pa.schema(
[
pa.field("id", pa.int64()),
# for dim=256, lance stores every 8 bits in a byte
# so the vector field should be a list of 256 / 8 = 32 bytes
pa.field("vector", pa.list_(pa.uint8(), 32)),
]
)
tbl = db.create_table("my_binary_vectors", schema=schema)
data = []
for i in range(1024):
vector = np.random.randint(0, 2, size=256)
# pack the binary vector into bytes to save space
packed_vector = np.packbits(vector)
data.append(
{
"id": i,
"vector": packed_vector,
}
)
tbl.add(data)
query = np.random.randint(0, 2, size=256)
packed_query = np.packbits(query)
tbl.search(packed_query).distance_type("hamming").to_arrow()
# --8<-- [end:search_binary_vectors]
def test_vs_enterprise_filtering(tmp_db, monkeypatch):
import sys
import types
dim = 384
rng = np.random.default_rng(0)
rows = [
{
"vector": rng.random(dim).astype("float32"),
"text": f"story {i}",
"keywords": f"kw{i}",
"label": i % 4,
}
for i in range(50)
]
tmp_db.create_table("lancedb-enterprise-quickstart", data=rows, mode="overwrite")
db = tmp_db
# Mock the Hugging Face dataset loader to avoid network downloads.
class _FakeDataset:
def __init__(self, n):
self._emb = [rng.random(dim).astype("float32") for _ in range(n)]
self._kw = [f"kw{i}" for i in range(n)]
def __getitem__(self, key):
if isinstance(key, str):
return {"keywords_embeddings": self._emb, "keywords": self._kw}[key]
return {"keywords": self._kw[key], "keywords_embeddings": self._emb[key]}
fake_datasets = types.ModuleType("datasets")
fake_datasets.load_dataset = lambda *a, **k: _FakeDataset(10)
monkeypatch.setitem(sys.modules, "datasets", fake_datasets)
# --8<-- [start:vector_search_prefilter]
from datasets import load_dataset
# Load query vector from dataset
query_dataset = load_dataset("sunhaozhepy/ag_news_sbert_keywords_embeddings", split="test[5000:5001]")
print(f"Query keywords: {query_dataset[0]['keywords']}")
query_embed = query_dataset["keywords_embeddings"][0]
# Open table and perform search
table_name = "lancedb-enterprise-quickstart"
table = db.open_table(table_name)
# Vector search with filters (pre-filtering is the default)
search_results = (
table.search(query_embed)
.where("label > 2")
.select(["text", "keywords", "label"])
.limit(5)
.to_pandas()
)
print("Search results (with pre-filtering):")
print(search_results)
# --8<-- [end:vector_search_prefilter]
# --8<-- [start:vector_search_postfilter]
results_post_filtered = (
table.search(query_embed)
.where("label > 1", prefilter=False)
.select(["text", "keywords", "label"])
.limit(5)
.to_pandas()
)
print("Vector search results with post-filter:")
print(results_post_filtered)
# --8<-- [end:vector_search_postfilter]
# --8<-- [start:batch_search]
# Load a batch of query embeddings
query_dataset = load_dataset(
"sunhaozhepy/ag_news_sbert_keywords_embeddings", split="test[5000:5005]"
)
query_embeds = query_dataset["keywords_embeddings"]
batch_results = table.search(query_embeds).limit(5).to_pandas()
print(batch_results)
# --8<-- [end:batch_search]
@pytest.mark.skip()
def test_hybrid_search():
# --8<-- [start:import-openai]
import openai
# --8<-- [end:import-openai]
# --8<-- [start:openai-embeddings]
# Ingest embedding function in LanceDB table
# Configuring the environment variable OPENAI_API_KEY
if "OPENAI_API_KEY" not in os.environ:
# OR set the key here as a variable
openai.api_key = "sk-..."
embeddings = get_registry().get("openai").create()
# --8<-- [end:openai-embeddings]
# --8<-- [start:class-Documents]
class Documents(LanceModel):
vector: Vector(embeddings.ndims()) = embeddings.VectorField()
text: str = embeddings.SourceField()
# --8<-- [end:class-Documents]
# --8<-- [start:basic_hybrid_search]
data = [
{"text": "rebel spaceships striking from a hidden base"},
{"text": "have won their first victory against the evil Galactic Empire"},
{"text": "during the battle rebel spies managed to steal secret plans"},
{"text": "to the Empire's ultimate weapon the Death Star"},
]
uri = "data/sample-lancedb"
db = lancedb.connect(uri)
table = db.create_table("documents", schema=Documents)
# ingest docs with auto-vectorization
table.add(data)
# Create a fts index before the hybrid search
table.create_fts_index("text")
# hybrid search with default re-ranker
table.search("flower moon", query_type="hybrid").to_pandas()
# --8<-- [end:basic_hybrid_search]
# --8<-- [start:hybrid_search_pass_vector_text]
vector_query = [0.1, 0.2, 0.3, 0.4, 0.5]
text_query = "flower moon"
(
table.search(query_type="hybrid")
.vector(vector_query)
.text(text_query)
.limit(5)
.to_pandas()
)
# --8<-- [end:hybrid_search_pass_vector_text]
@pytest.mark.skip
async def test_hybrid_search_async():
import openai
# --8<-- [start:openai-embeddings]
# Ingest embedding function in LanceDB table
# Configuring the environment variable OPENAI_API_KEY
if "OPENAI_API_KEY" not in os.environ:
# OR set the key here as a variable
openai.api_key = "sk-..."
embeddings = get_registry().get("openai").create()
# --8<-- [end:openai-embeddings]
# --8<-- [start:class-Documents]
class Documents(LanceModel):
vector: Vector(embeddings.ndims()) = embeddings.VectorField()
text: str = embeddings.SourceField()
# --8<-- [end:class-Documents]
# --8<-- [start:basic_hybrid_search_async]
uri = "data/sample-lancedb"
async_db = await lancedb.connect_async(uri)
data = [
{"text": "rebel spaceships striking from a hidden base"},
{"text": "have won their first victory against the evil Galactic Empire"},
{"text": "during the battle rebel spies managed to steal secret plans"},
{"text": "to the Empire's ultimate weapon the Death Star"},
]
async_tbl = await async_db.create_table("documents_async", schema=Documents)
# ingest docs with auto-vectorization
await async_tbl.add(data)
# Create a fts index before the hybrid search
await async_tbl.create_index("text", config=FTS())
text_query = "flower moon"
# hybrid search with default re-ranker
await (await async_tbl.search("flower moon", query_type="hybrid")).to_pandas()
# --8<-- [end:basic_hybrid_search_async]
# --8<-- [start:hybrid_search_pass_vector_text_async]
vector_query = [0.1, 0.2, 0.3, 0.4, 0.5]
text_query = "flower moon"
await (
async_tbl.query()
.nearest_to(vector_query)
.nearest_to_text(text_query)
.limit(5)
.to_pandas()
)
# --8<-- [end:hybrid_search_pass_vector_text_async]