Files
lancedb/python/tests/test_query.py
Chang She 3c46d7f268 Handle NaN input data (#241)
Sometimes LangChain would insert a single `[np.nan]` as a placeholder if
the embedding function failed. This causes a problem for Lance format
because then the array can't be stored as a FixedSizedListArray.

Instead:
1. By default we remove rows with embedding lengths less than the
maximum length in the batch
2. If `strict=True` kwargs is set to True, then a `ValueError` is raised
if the embeddings aren't all the same length

---------

Co-authored-by: Chang She <chang@lancedb.com>
2023-07-04 20:00:46 -07:00

116 lines
3.3 KiB
Python

# Copyright 2023 LanceDB Developers
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import unittest.mock as mock
import lance
import numpy as np
import pandas.testing as tm
import pyarrow as pa
import pytest
from lancedb.db import LanceDBConnection
from lancedb.query import LanceQueryBuilder
from lancedb.table import LanceTable
class MockTable:
def __init__(self, tmp_path):
self.uri = tmp_path
self._conn = LanceDBConnection("/tmp/lance/")
def to_lance(self):
return lance.dataset(self.uri)
@pytest.fixture
def table(tmp_path) -> MockTable:
df = pa.table(
{
"vector": pa.array(
[[1, 2], [3, 4]], type=pa.list_(pa.float32(), list_size=2)
),
"id": pa.array([1, 2]),
"str_field": pa.array(["a", "b"]),
"float_field": pa.array([1.0, 2.0]),
}
)
lance.write_dataset(df, tmp_path)
return MockTable(tmp_path)
def test_query_builder(table):
df = LanceQueryBuilder(table, [0, 0], "vector").limit(1).select(["id"]).to_df()
assert df["id"].values[0] == 1
assert all(df["vector"].values[0] == [1, 2])
def test_query_builder_with_filter(table):
df = LanceQueryBuilder(table, [0, 0], "vector").where("id = 2").to_df()
assert df["id"].values[0] == 2
assert all(df["vector"].values[0] == [3, 4])
def test_query_builder_with_metric(table):
query = [4, 8]
vector_column_name = "vector"
df_default = LanceQueryBuilder(table, query, vector_column_name).to_df()
df_l2 = LanceQueryBuilder(table, query, vector_column_name).metric("L2").to_df()
tm.assert_frame_equal(df_default, df_l2)
df_cosine = (
LanceQueryBuilder(table, query, vector_column_name)
.metric("cosine")
.limit(1)
.to_df()
)
assert df_cosine.score[0] == pytest.approx(
cosine_distance(query, df_cosine.vector[0]),
abs=1e-6,
)
assert 0 <= df_cosine.score[0] <= 1
def test_query_builder_with_different_vector_column():
table = mock.MagicMock(spec=LanceTable)
query = [4, 8]
vector_column_name = "foo_vector"
builder = (
LanceQueryBuilder(table, query, vector_column_name)
.metric("cosine")
.where("b < 10")
.select(["b"])
.limit(2)
)
ds = mock.Mock()
table.to_lance.return_value = ds
table._conn = mock.MagicMock()
table._conn.is_managed_remote = False
builder.to_arrow()
ds.to_table.assert_called_once_with(
columns=["b"],
filter="b < 10",
nearest={
"column": vector_column_name,
"q": query,
"k": 2,
"metric": "cosine",
"nprobes": 20,
"refine_factor": None,
},
)
def cosine_distance(vec1, vec2):
return 1 - np.dot(vec1, vec2) / (np.linalg.norm(vec1) * np.linalg.norm(vec2))