以编程方式使用文档

>Activeloop Deep Lake 作为多模态向量存储,存储嵌入向量及其元数据,包括文本、JSON、图像、音频、视频等。它将数据保存在本地、您的云端或 Activeloop 存储中。它执行包括嵌入向量及其属性的混合搜索。

本笔记本展示与 Activeloop Deep Lake相关的基本功能。虽然 Deep Lake 可以存储嵌入向量,但它能够存储任何类型的数据。它是一个无服务器数据湖,具有版本控制、查询引擎和面向深度学习框架的流式数据加载器。

欲了解更多详情,请参阅 Deep Lake 文档

设置

pip install -qU  langchain-openai langchain-deeplake tiktoken

由 activeloop 提供的示例

与 LangChain 集成.

本地 Deep Lake

from langchain_deeplake.vectorstores import DeeplakeVectorStore
from langchain_openai import OpenAIEmbeddings
from langchain_text_splitters import CharacterTextSplitter
if "OPENAI_API_KEY" not in os.environ:
    os.environ["OPENAI_API_KEY"] = getpass.getpass("OpenAI API Key:")

if "ACTIVELOOP_TOKEN" not in os.environ:
    os.environ["ACTIVELOOP_TOKEN"] = getpass.getpass("activeloop token:")
from langchain_community.document_loaders import TextLoader

loader = TextLoader("../../how_to/state_of_the_union.txt")
documents = loader.load()
text_splitter = CharacterTextSplitter(chunk_size=1000, chunk_overlap=0)
docs = text_splitter.split_documents(documents)

embeddings = OpenAIEmbeddings()

创建本地数据集

在以下位置创建本地数据集 ./my_deeplake/,然后运行相似性搜索。Deeplake+LangChain 集成在后台使用 Deep Lake 数据集,因此 datasetvector store 可以互换使用。要在您自己的云中或 Deep Lake 存储中创建数据集, 请相应调整路径.

db = DeeplakeVectorStore(
    dataset_path="./my_deeplake/", embedding_function=embeddings, overwrite=True
)
db.add_documents(docs)
# or shorter
# db = DeepLake.from_documents(docs, dataset_path="./my_deeplake/", embedding_function=embeddings, overwrite=True)

查询数据集

query = "What did the president say about Ketanji Brown Jackson"
docs = db.similarity_search(query)
print(docs[0].page_content)

之后,您可以重新加载数据集而无需重新计算嵌入向量

db = DeeplakeVectorStore(
    dataset_path="./my_deeplake/", embedding_function=embeddings, read_only=True
)
docs = db.similarity_search(query)

设置 read_only=True 可在不需要更新时防止对向量存储进行意外修改。这确保数据保持不变,除非明确打算更改。通常最佳做法是指定此参数以避免意外更新。

Retrieval Question/Answering

from langchain_classic.chains import RetrievalQA
from langchain_openai import ChatOpenAI

qa = RetrievalQA.from_chain_type(
    llm=ChatOpenAI(model="gpt-3.5-turbo"),
    chain_type="stuff",
    retriever=db.as_retriever(),
)
query = "What did the president say about Ketanji Brown Jackson"
qa.run(query)

元数据中基于属性的过滤

让我们创建另一个包含元数据的向量存储,其中包含文档创建年份。

for d in docs:
    d.metadata["year"] = random.randint(2012, 2014)

db = DeeplakeVectorStore.from_documents(
    docs, embeddings, dataset_path="./my_deeplake/", overwrite=True
)
db.similarity_search(
    "What did the president say about Ketanji Brown Jackson",
    filter={"metadata": {"year": 2013}},
)

选择距离函数

距离函数 L2 表示欧几里得距离, cos 表示余弦相似度

db.similarity_search(
    "What did the president say about Ketanji Brown Jackson?", distance_metric="l2"
)

最大边际相关性

使用最大边际相关性

db.max_marginal_relevance_search(
    "What did the president say about Ketanji Brown Jackson?"
)

删除数据集

db.delete_dataset()

云上的 Deep Lake 数据集(Activeloop、AWS、GCS 等)或内存中的数据集

默认情况下,Deep Lake 数据集存储在本地。要将它们存储在内存中、Deep Lake 托管数据库中或任何对象存储中,您可以提供 创建向量存储时的相应路径和凭证。某些路径需要注册 Activeloop 并创建 API 令牌,可在此处 获取

os.environ["ACTIVELOOP_TOKEN"] = activeloop_token
# Embed and store the texts
username = ""  # your username on app.activeloop.ai
dataset_path = f"hub://{username}/langchain_testing_python"  # could be also ./local/path (much faster locally), s3://bucket/path/to/dataset, gcs://path/to/dataset, etc.

docs = text_splitter.split_documents(documents)

embedding = OpenAIEmbeddings()
db = DeeplakeVectorStore(
    dataset_path=dataset_path, embedding_function=embeddings, overwrite=True
)
ids = db.add_documents(docs)
query = "What did the president say about Ketanji Brown Jackson"
docs = db.similarity_search(query)
print(docs[0].page_content)
# Embed and store the texts
username = ""  # your username on app.activeloop.ai
dataset_path = f"hub://{username}/langchain_testing"

docs = text_splitter.split_documents(documents)

embedding = OpenAIEmbeddings()
db = DeeplakeVectorStore(
    dataset_path=dataset_path,
    embedding_function=embeddings,
    overwrite=True,
)
ids = db.add_documents(docs)

TQL 搜索

此外,在相似性_搜索方法中支持查询执行,可利用 Deep Lake 的张量查询语言 (TQL) 指定查询。

search_id = db.dataset["ids"][0]
docs = db.similarity_search(
    query=None,
    tql=f"SELECT * WHERE ids == '{search_id}'",
)
db.dataset.summary()

在 AWS S3 上创建向量存储

dataset_path = "s3://BUCKET/langchain_test"  # could be also ./local/path (much faster locally), hub://bucket/path/to/dataset, gcs://path/to/dataset, etc.

embedding = OpenAIEmbeddings()
db = DeeplakeVectorStore.from_documents(
    docs,
    dataset_path=dataset_path,
    embedding=embeddings,
    overwrite=True,
    creds={
        "aws_access_key_id": os.environ["AWS_ACCESS_KEY_ID"],
        "aws_secret_access_key": os.environ["AWS_SECRET_ACCESS_KEY"],
        "aws_session_token": os.environ["AWS_SESSION_TOKEN"],  # Optional
    },
)

Deep Lake API

您可以在以下位置访问 Deep Lake 数据集 db.vectorstore

# get structure of the dataset
db.dataset.summary()
# get embeddings numpy array
embeds = db.dataset["embeddings"][:]

将本地数据集传输到云端

复制已创建的数据集到云端。您也可以从云端传输到本地。

username = ""  # your username on app.activeloop.ai
source = f"hub://{username}/langchain_testing"  # could be local, s3, gcs, etc.
destination = f"hub://{username}/langchain_test_copy"  # could be local, s3, gcs, etc.


deeplake.copy(src=source, dst=destination)
db = DeeplakeVectorStore(dataset_path=destination, embedding_function=embeddings)
db.add_documents(docs)