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LanceDB

LanceDBVectorStore #

基础:BasePydanticVectorStore

LanceDB 向量存储。

在 LanceDB 中存储文本和嵌入。如果 LanceDB 数据集不存在,向量存储将打开现有数据集或创建新数据集。

参数

名称 类型 描述 默认值
uri (字符串, 必填)

LanceDB 存储文件的位置。

'/tmp/lancedb'
table_name 字符串

存储嵌入的表名。默认为 "vectors"。

'vectors'
vector_column_name 字符串

表中向量列的名称,如果与默认值不同。默认为 "vector",与 lancedb 约定一致。

'vector'
nprobes 整数

使用的探测次数。数值越高,搜索越准确,但也越慢。默认为 20。

20
refine_factor 可选[整数]

(整数, 可选): 通过读取额外元素并在内存中重新排序来优化结果。默认为 None

text_key 字符串

表中包含文本的键。默认为 "text"。

DEFAULT_TEXT_KEY
doc_id_key 字符串

表中包含文档 ID 的键。默认为 "doc_id"。

DEFAULT_DOC_ID_KEY
connection Any

用于 LanceDB 的连接。默认为 None。

table Any

用于 LanceDB 的表。默认为 None。

api_key 字符串

用于 LanceDB 云的 API 密钥。默认为 None。您也可以设置 LANCE_API_KEY 环境变量。

region 字符串

用于您的 LanceDB 云数据库的区域。默认为 None。

mode 字符串

用于 LanceDB 的模式。默认为 "overwrite"。

'overwrite'
query_type 字符串

用于 LanceDB 的查询类型。默认为 "vector"。

'vector'
reranker Any

用于 LanceDB 的重新排序器。默认为 None。

overfetch_factor 整数

获取更多结果的倍数因子。默认为 1。

1

抛出

类型 描述
ImportError

无法导入 lancedb

返回值

名称 类型 描述
LanceDBVectorStore

支持创建 LanceDB 数据集并进行查询的 VectorStore。

示例

pip install llama-index-vector-stores-lancedb

from llama_index.vector_stores.lancedb import LanceDBVectorStore

vector_store = LanceDBVectorStore()  # native invocation
源代码位于 llama-index-integrations/vector_stores/llama-index-vector-stores-lancedb/llama_index/vector_stores/lancedb/base.py
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class LanceDBVectorStore(BasePydanticVectorStore):
    """
    The LanceDB Vector Store.

    Stores text and embeddings in LanceDB. The vector store will open an existing
        LanceDB dataset or create the dataset if it does not exist.

    Args:
        uri (str, required): Location where LanceDB will store its files.
        table_name (str, optional): The table name where the embeddings will be stored.
            Defaults to "vectors".
        vector_column_name (str, optional): The vector column name in the table if different from default.
            Defaults to "vector", in keeping with lancedb convention.
        nprobes (int, optional): The number of probes used.
            A higher number makes search more accurate but also slower.
            Defaults to 20.
        refine_factor: (int, optional): Refine the results by reading extra elements
            and re-ranking them in memory.
            Defaults to None
        text_key (str, optional): The key in the table that contains the text.
            Defaults to "text".
        doc_id_key (str, optional): The key in the table that contains the document id.
            Defaults to "doc_id".
        connection (Any, optional): The connection to use for LanceDB.
            Defaults to None.
        table (Any, optional): The table to use for LanceDB.
            Defaults to None.
        api_key (str, optional): The API key to use LanceDB cloud.
            Defaults to None. You can also set the `LANCE_API_KEY` environment variable.
        region (str, optional): The region to use for your LanceDB cloud db.
            Defaults to None.
        mode (str, optional): The mode to use for LanceDB.
            Defaults to "overwrite".
        query_type (str, optional): The type of query to use for LanceDB.
            Defaults to "vector".
        reranker (Any, optional): The reranker to use for LanceDB.
            Defaults to None.
        overfetch_factor (int, optional): The factor by which to fetch more results.
            Defaults to 1.

    Raises:
        ImportError: Unable to import `lancedb`.

    Returns:
        LanceDBVectorStore: VectorStore that supports creating LanceDB datasets and
            querying it.

    Examples:
        `pip install llama-index-vector-stores-lancedb`

        ```python
        from llama_index.vector_stores.lancedb import LanceDBVectorStore

        vector_store = LanceDBVectorStore()  # native invocation
        ```

    """

    stores_text: bool = True
    flat_metadata: bool = True
    uri: Optional[str]
    vector_column_name: Optional[str]
    nprobes: Optional[int]
    refine_factor: Optional[int]
    text_key: Optional[str]
    doc_id_key: Optional[str]
    api_key: Optional[str]
    region: Optional[str]
    mode: Optional[str]
    query_type: Optional[str]
    overfetch_factor: Optional[int]

    _table_name: Optional[str] = PrivateAttr()
    _connection: lancedb.DBConnection = PrivateAttr()
    _table: Any = PrivateAttr()
    _metadata_keys: Any = PrivateAttr()
    _fts_index: Any = PrivateAttr()
    _reranker: Any = PrivateAttr()

    def __init__(
        self,
        uri: Optional[str] = "/tmp/lancedb",
        table_name: Optional[str] = "vectors",
        vector_column_name: str = "vector",
        nprobes: int = 20,
        refine_factor: Optional[int] = None,
        text_key: str = DEFAULT_TEXT_KEY,
        doc_id_key: str = DEFAULT_DOC_ID_KEY,
        connection: Optional[Any] = None,
        table: Optional[Any] = None,
        api_key: Optional[str] = None,
        region: Optional[str] = None,
        mode: str = "overwrite",
        query_type: str = "vector",
        reranker: Optional[Any] = None,
        overfetch_factor: int = 1,
        **kwargs: Any,
    ) -> None:
        """Init params."""
        super().__init__(
            uri=uri,
            table_name=table_name,
            vector_column_name=vector_column_name,
            nprobes=nprobes,
            refine_factor=refine_factor,
            text_key=text_key,
            doc_id_key=doc_id_key,
            mode=mode,
            query_type=query_type,
            overfetch_factor=overfetch_factor,
            api_key=api_key,
            region=region,
            **kwargs,
        )

        self._table_name = table_name
        self._metadata_keys = None
        self._fts_index = None

        if isinstance(reranker, lancedb.rerankers.Reranker):
            self._reranker = reranker
        elif reranker is None:
            self._reranker = None
        else:
            raise ValueError(
                "`reranker` has to be a lancedb.rerankers.Reranker object."
            )

        if isinstance(connection, lancedb.db.LanceDBConnection):
            self._connection = connection
        elif isinstance(connection, str):
            raise ValueError(
                "`connection` has to be a lancedb.db.LanceDBConnection object."
            )
        else:
            if api_key is None and os.getenv("LANCE_API_KEY") is None:
                if uri.startswith("db://"):
                    raise ValueError("API key is required for LanceDB cloud.")
                else:
                    self._connection = lancedb.connect(uri)
            else:
                if "db://" not in uri:
                    self._connection = lancedb.connect(uri)
                    warnings.warn(
                        "api key provided with local uri. The data will be stored locally"
                    )
                self._connection = lancedb.connect(
                    uri, api_key=api_key or os.getenv("LANCE_API_KEY"), region=region
                )

        if table is not None:
            try:
                assert isinstance(
                    table, (lancedb.db.LanceTable, lancedb.remote.table.RemoteTable)
                )
                self._table = table
                self._table_name = (
                    table.name if hasattr(table, "name") else "remote_table"
                )
            except AssertionError:
                raise ValueError(
                    "`table` has to be a lancedb.db.LanceTable or lancedb.remote.table.RemoteTable object."
                )
        else:
            try:
                if self._table_exists() and self.mode != "overwrite":
                    self._table = self._connection.open_table(table_name)
                else:
                    self._table = None
            except ValueError:
                self._table = None

    @property
    def client(self) -> None:
        """Get client."""
        return self._connection

    @classmethod
    def from_table(cls, table: Any) -> "LanceDBVectorStore":
        """Create instance from table."""
        try:
            if not isinstance(
                table, (lancedb.db.LanceTable, lancedb.remote.table.RemoteTable)
            ):
                raise Exception("argument is not lancedb table instance")
            return cls(table=table)
        except Exception as e:
            print("ldb version", lancedb.__version__)
            raise

    def _add_reranker(self, reranker: lancedb.rerankers.Reranker) -> None:
        """Add a reranker to an existing vector store."""
        if reranker is None:
            raise ValueError(
                "`reranker` has to be a lancedb.rerankers.Reranker object."
            )
        self._reranker = reranker

    def _table_exists(self, tbl_name: Optional[str] = None) -> bool:
        return (tbl_name or self._table_name) in self._connection.table_names()

    def create_index(
        self,
        scalar: Optional[bool] = False,
        col_name: Optional[str] = None,
        num_partitions: Optional[int] = 256,
        num_sub_vectors: Optional[int] = 96,
        index_cache_size: Optional[int] = None,
        metric: Optional[str] = "L2",
    ) -> None:
        """
        Create a scalar(for non-vector cols) or a vector index on a table.
        Make sure your vector column has enough data before creating an index on it.

        Args:
            scalar: Create a scalar index on a column. Defaults to False
            col_name: The column name to create the scalar index on. Defaults to None
            num_partitions: Number of partitions to use for the index. Defaults to 256
            num_sub_vectors: Number of sub-vectors to use for the index. Defaults to 96
            index_cache_size: The size of the index cache. Defaults to None
            metric: Provide the metric to use for vector index. Defaults to 'L2'
                    choice of metrics: 'L2', 'dot', 'cosine'
        Returns:
            None

        """
        if scalar is None:
            self._table.create_index(
                metric=metric,
                vector_column_name=self.vector_column_name,
                num_partitions=num_partitions,
                num_sub_vectors=num_sub_vectors,
                index_cache_size=index_cache_size,
            )
        else:
            if col_name is None:
                raise ValueError("Column name is required for scalar index creation.")
            self._table.create_scalar_index(col_name)

    def add(
        self,
        nodes: List[BaseNode],
        **add_kwargs: Any,
    ) -> List[str]:
        if not nodes:
            _logger.debug("No nodes to add. Skipping the database operation.")
            return []
        data = []
        ids = []

        for node in nodes:
            metadata = node_to_metadata_dict(
                node, remove_text=False, flat_metadata=self.flat_metadata
            )
            if not self._metadata_keys:
                self._metadata_keys = list(metadata.keys())
            append_data = {
                "id": node.node_id,
                self.doc_id_key: node.ref_doc_id,
                self.vector_column_name: node.get_embedding(),
                self.text_key: node.get_content(metadata_mode=MetadataMode.NONE),
                "metadata": metadata,
            }
            data.append(append_data)
            ids.append(node.node_id)

        if self._table is None:
            self._table = self._connection.create_table(
                self._table_name, data, mode=self.mode
            )
        else:
            if self.api_key is None:
                self._table.add(data)
            else:
                self._table.add(data)

        self._fts_index = None  # reset fts index

        return ids

    def delete(self, ref_doc_id: str, **delete_kwargs: Any) -> None:
        """
        Delete nodes using with ref_doc_id.

        Args:
            ref_doc_id (str): The doc_id of the document to delete.

        """
        self._table.delete(f'{self.doc_id_key} = "' + ref_doc_id + '"')

    def delete_nodes(self, node_ids: List[str], **delete_kwargs: Any) -> None:
        """
        Delete nodes using with node_ids.

        Args:
            node_ids (List[str]): The list of node_ids to delete.

        """
        self._table.delete('id in ("' + '","'.join(node_ids) + '")')

    def get_nodes(
        self,
        node_ids: Optional[List[str]] = None,
        filters: Optional[MetadataFilters] = None,
        **kwargs: Any,
    ) -> List[BaseNode]:
        """
        Get nodes from the vector store.
        """
        if isinstance(self._table, lancedb.remote.table.RemoteTable):
            raise ValueError("get_nodes is not supported for LanceDB cloud yet.")

        if filters is not None:
            if "where" in kwargs:
                raise ValueError(
                    "Cannot specify filter via both query and kwargs. "
                    "Use kwargs only for lancedb specific items that are "
                    "not supported via the generic query interface."
                )
            where = _to_lance_filter(filters, self._metadata_keys)
        else:
            where = kwargs.pop("where", None)

        if node_ids is not None:
            where = f'id in ("' + '","'.join(node_ids) + '")'

        results = self._table.search().where(where).to_pandas()

        nodes = []

        for _, item in results.iterrows():
            try:
                node = metadata_dict_to_node(item.metadata)
                node.embedding = list(item[self.vector_column_name])
            except Exception:
                # deprecated legacy logic for backward compatibility
                _logger.debug(
                    "Failed to parse Node metadata, fallback to legacy logic."
                )
                if item.metadata:
                    metadata, node_info, _relation = legacy_metadata_dict_to_node(
                        item.metadata, text_key=self.text_key
                    )
                else:
                    metadata, node_info = {}, {}
                node = TextNode(
                    text=item[self.text_key] or "",
                    id_=item.id,
                    metadata=metadata,
                    start_char_idx=node_info.get("start", None),
                    end_char_idx=node_info.get("end", None),
                    relationships={
                        NodeRelationship.SOURCE: RelatedNodeInfo(
                            node_id=item[self.doc_id_key]
                        ),
                    },
                )

            nodes.append(node)

        return nodes

    def query(
        self,
        query: VectorStoreQuery,
        **kwargs: Any,
    ) -> VectorStoreQueryResult:
        """Query index for top k most similar nodes."""
        if query.filters is not None:
            if "where" in kwargs:
                raise ValueError(
                    "Cannot specify filter via both query and kwargs. "
                    "Use kwargs only for lancedb specific items that are "
                    "not supported via the generic query interface."
                )
            where = _to_lance_filter(query.filters, self._metadata_keys)
        else:
            where = kwargs.pop("where", None)

        query_type = kwargs.pop("query_type", self.query_type)

        _logger.info(f"query_type :, {query_type}")

        if query_type == "vector":
            _query = query.query_embedding
        else:
            if not isinstance(self._table, lancedb.db.LanceTable):
                raise ValueError(
                    "creating FTS index is not supported for LanceDB Cloud yet. "
                    "Please use a local table for FTS/Hybrid search."
                )
            if self._fts_index is None:
                self._fts_index = self._table.create_fts_index(
                    self.text_key, replace=True
                )

            if query_type == "hybrid":
                _query = (query.query_embedding, query.query_str)
            elif query_type == "fts":
                _query = query.query_str
            else:
                raise ValueError(f"Invalid query type: {query_type}")

        if query_type == "hybrid":
            lance_query = (
                self._table.search(
                    vector_column_name=self.vector_column_name, query_type="hybrid"
                )
                .vector(query.query_embedding)
                .text(query.query_str)
            )
        else:
            lance_query = self._table.search(
                query=_query,
                vector_column_name=self.vector_column_name,
            )
        lance_query.limit(query.similarity_top_k * self.overfetch_factor).where(where)

        if query_type != "fts":
            lance_query.nprobes(self.nprobes)
            if query_type == "hybrid" and self._reranker is not None:
                _logger.info(f"using {self._reranker} for reranking results.")
                lance_query.rerank(reranker=self._reranker)

        if self.refine_factor is not None:
            lance_query.refine_factor(self.refine_factor)

        results = lance_query.to_pandas()

        if len(results) == 0:
            raise Warning("query results are empty..")

        nodes = []

        for _, item in results.iterrows():
            try:
                node = metadata_dict_to_node(item.metadata)
                node.embedding = list(item[self.vector_column_name])
            except Exception:
                # deprecated legacy logic for backward compatibility
                _logger.debug(
                    "Failed to parse Node metadata, fallback to legacy logic."
                )
                if item.metadata:
                    metadata, node_info, _relation = legacy_metadata_dict_to_node(
                        item.metadata, text_key=self.text_key
                    )
                else:
                    metadata, node_info = {}, {}
                node = TextNode(
                    text=item[self.text_key] or "",
                    id_=item.id,
                    metadata=metadata,
                    start_char_idx=node_info.get("start", None),
                    end_char_idx=node_info.get("end", None),
                    relationships={
                        NodeRelationship.SOURCE: RelatedNodeInfo(
                            node_id=item[self.doc_id_key]
                        ),
                    },
                )

            nodes.append(node)

        return VectorStoreQueryResult(
            nodes=nodes,
            similarities=_to_llama_similarities(results),
            ids=results["id"].tolist(),
        )

client property #

client: None

获取客户端。

from_table classmethod #

from_table(table: Any) -> LanceDBVectorStore

从表创建实例。

源代码位于 llama-index-integrations/vector_stores/llama-index-vector-stores-lancedb/llama_index/vector_stores/lancedb/base.py
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@classmethod
def from_table(cls, table: Any) -> "LanceDBVectorStore":
    """Create instance from table."""
    try:
        if not isinstance(
            table, (lancedb.db.LanceTable, lancedb.remote.table.RemoteTable)
        ):
            raise Exception("argument is not lancedb table instance")
        return cls(table=table)
    except Exception as e:
        print("ldb version", lancedb.__version__)
        raise

create_index #

create_index(scalar: Optional[bool] = False, col_name: Optional[str] = None, num_partitions: Optional[int] = 256, num_sub_vectors: Optional[int] = 96, index_cache_size: Optional[int] = None, metric: Optional[str] = 'L2') -> None

在表上创建标量(用于非向量列)或向量索引。在向量列上创建索引之前,请确保该列包含足够的数据。

参数

名称 类型 描述 默认值
scalar 可选[布尔值]

在列上创建标量索引。默认为 False

False
col_name 可选[字符串]

创建标量索引的列名。默认为 None

num_partitions 可选[整数]

用于索引的分区数。默认为 256

256
num_sub_vectors 可选[整数]

用于索引的子向量数。默认为 96

96
index_cache_size 可选[整数]

索引缓存的大小。默认为 None

metric 可选[字符串]

提供用于向量索引的度量。默认为 'L2'。可选度量:'L2', 'dot', 'cosine'

'L2'

返回值:None

源代码位于 llama-index-integrations/vector_stores/llama-index-vector-stores-lancedb/llama_index/vector_stores/lancedb/base.py
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def create_index(
    self,
    scalar: Optional[bool] = False,
    col_name: Optional[str] = None,
    num_partitions: Optional[int] = 256,
    num_sub_vectors: Optional[int] = 96,
    index_cache_size: Optional[int] = None,
    metric: Optional[str] = "L2",
) -> None:
    """
    Create a scalar(for non-vector cols) or a vector index on a table.
    Make sure your vector column has enough data before creating an index on it.

    Args:
        scalar: Create a scalar index on a column. Defaults to False
        col_name: The column name to create the scalar index on. Defaults to None
        num_partitions: Number of partitions to use for the index. Defaults to 256
        num_sub_vectors: Number of sub-vectors to use for the index. Defaults to 96
        index_cache_size: The size of the index cache. Defaults to None
        metric: Provide the metric to use for vector index. Defaults to 'L2'
                choice of metrics: 'L2', 'dot', 'cosine'
    Returns:
        None

    """
    if scalar is None:
        self._table.create_index(
            metric=metric,
            vector_column_name=self.vector_column_name,
            num_partitions=num_partitions,
            num_sub_vectors=num_sub_vectors,
            index_cache_size=index_cache_size,
        )
    else:
        if col_name is None:
            raise ValueError("Column name is required for scalar index creation.")
        self._table.create_scalar_index(col_name)

delete #

delete(ref_doc_id: str, **delete_kwargs: Any) -> None

使用 ref_doc_id 删除节点。

参数

名称 类型 描述 默认值
ref_doc_id 字符串

要删除文档的 doc_id。

必填
源代码位于 llama-index-integrations/vector_stores/llama-index-vector-stores-lancedb/llama_index/vector_stores/lancedb/base.py
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def delete(self, ref_doc_id: str, **delete_kwargs: Any) -> None:
    """
    Delete nodes using with ref_doc_id.

    Args:
        ref_doc_id (str): The doc_id of the document to delete.

    """
    self._table.delete(f'{self.doc_id_key} = "' + ref_doc_id + '"')

delete_nodes #

delete_nodes(node_ids: List[str], **delete_kwargs: Any) -> None

使用 node_ids 删除节点。

参数

名称 类型 描述 默认值
node_ids 列表[字符串]

要删除的 node_ids 列表。

必填
源代码位于 llama-index-integrations/vector_stores/llama-index-vector-stores-lancedb/llama_index/vector_stores/lancedb/base.py
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def delete_nodes(self, node_ids: List[str], **delete_kwargs: Any) -> None:
    """
    Delete nodes using with node_ids.

    Args:
        node_ids (List[str]): The list of node_ids to delete.

    """
    self._table.delete('id in ("' + '","'.join(node_ids) + '")')

get_nodes #

get_nodes(node_ids: Optional[List[str]] = None, filters: Optional[MetadataFilters] = None, **kwargs: Any) -> List[BaseNode]

从向量存储获取节点。

源代码位于 llama-index-integrations/vector_stores/llama-index-vector-stores-lancedb/llama_index/vector_stores/lancedb/base.py
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def get_nodes(
    self,
    node_ids: Optional[List[str]] = None,
    filters: Optional[MetadataFilters] = None,
    **kwargs: Any,
) -> List[BaseNode]:
    """
    Get nodes from the vector store.
    """
    if isinstance(self._table, lancedb.remote.table.RemoteTable):
        raise ValueError("get_nodes is not supported for LanceDB cloud yet.")

    if filters is not None:
        if "where" in kwargs:
            raise ValueError(
                "Cannot specify filter via both query and kwargs. "
                "Use kwargs only for lancedb specific items that are "
                "not supported via the generic query interface."
            )
        where = _to_lance_filter(filters, self._metadata_keys)
    else:
        where = kwargs.pop("where", None)

    if node_ids is not None:
        where = f'id in ("' + '","'.join(node_ids) + '")'

    results = self._table.search().where(where).to_pandas()

    nodes = []

    for _, item in results.iterrows():
        try:
            node = metadata_dict_to_node(item.metadata)
            node.embedding = list(item[self.vector_column_name])
        except Exception:
            # deprecated legacy logic for backward compatibility
            _logger.debug(
                "Failed to parse Node metadata, fallback to legacy logic."
            )
            if item.metadata:
                metadata, node_info, _relation = legacy_metadata_dict_to_node(
                    item.metadata, text_key=self.text_key
                )
            else:
                metadata, node_info = {}, {}
            node = TextNode(
                text=item[self.text_key] or "",
                id_=item.id,
                metadata=metadata,
                start_char_idx=node_info.get("start", None),
                end_char_idx=node_info.get("end", None),
                relationships={
                    NodeRelationship.SOURCE: RelatedNodeInfo(
                        node_id=item[self.doc_id_key]
                    ),
                },
            )

        nodes.append(node)

    return nodes

query #

query(query: VectorStoreQuery, **kwargs: Any) -> VectorStoreQueryResult

查询索引以获取相似度最高的 k 个节点。

源代码位于 llama-index-integrations/vector_stores/llama-index-vector-stores-lancedb/llama_index/vector_stores/lancedb/base.py
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def query(
    self,
    query: VectorStoreQuery,
    **kwargs: Any,
) -> VectorStoreQueryResult:
    """Query index for top k most similar nodes."""
    if query.filters is not None:
        if "where" in kwargs:
            raise ValueError(
                "Cannot specify filter via both query and kwargs. "
                "Use kwargs only for lancedb specific items that are "
                "not supported via the generic query interface."
            )
        where = _to_lance_filter(query.filters, self._metadata_keys)
    else:
        where = kwargs.pop("where", None)

    query_type = kwargs.pop("query_type", self.query_type)

    _logger.info(f"query_type :, {query_type}")

    if query_type == "vector":
        _query = query.query_embedding
    else:
        if not isinstance(self._table, lancedb.db.LanceTable):
            raise ValueError(
                "creating FTS index is not supported for LanceDB Cloud yet. "
                "Please use a local table for FTS/Hybrid search."
            )
        if self._fts_index is None:
            self._fts_index = self._table.create_fts_index(
                self.text_key, replace=True
            )

        if query_type == "hybrid":
            _query = (query.query_embedding, query.query_str)
        elif query_type == "fts":
            _query = query.query_str
        else:
            raise ValueError(f"Invalid query type: {query_type}")

    if query_type == "hybrid":
        lance_query = (
            self._table.search(
                vector_column_name=self.vector_column_name, query_type="hybrid"
            )
            .vector(query.query_embedding)
            .text(query.query_str)
        )
    else:
        lance_query = self._table.search(
            query=_query,
            vector_column_name=self.vector_column_name,
        )
    lance_query.limit(query.similarity_top_k * self.overfetch_factor).where(where)

    if query_type != "fts":
        lance_query.nprobes(self.nprobes)
        if query_type == "hybrid" and self._reranker is not None:
            _logger.info(f"using {self._reranker} for reranking results.")
            lance_query.rerank(reranker=self._reranker)

    if self.refine_factor is not None:
        lance_query.refine_factor(self.refine_factor)

    results = lance_query.to_pandas()

    if len(results) == 0:
        raise Warning("query results are empty..")

    nodes = []

    for _, item in results.iterrows():
        try:
            node = metadata_dict_to_node(item.metadata)
            node.embedding = list(item[self.vector_column_name])
        except Exception:
            # deprecated legacy logic for backward compatibility
            _logger.debug(
                "Failed to parse Node metadata, fallback to legacy logic."
            )
            if item.metadata:
                metadata, node_info, _relation = legacy_metadata_dict_to_node(
                    item.metadata, text_key=self.text_key
                )
            else:
                metadata, node_info = {}, {}
            node = TextNode(
                text=item[self.text_key] or "",
                id_=item.id,
                metadata=metadata,
                start_char_idx=node_info.get("start", None),
                end_char_idx=node_info.get("end", None),
                relationships={
                    NodeRelationship.SOURCE: RelatedNodeInfo(
                        node_id=item[self.doc_id_key]
                    ),
                },
            )

        nodes.append(node)

    return VectorStoreQueryResult(
        nodes=nodes,
        similarities=_to_llama_similarities(results),
        ids=results["id"].tolist(),
    )