Google BigQuery Vector Search
Google Cloud BigQuery Vector Search lets you use GoogleSQL to do semantic search, using vector indexes for fast approximate results, or using brute force for exact results.
This tutorial illustrates how to work with an end-to-end data and embedding management system in LangChain, and provides a scalable semantic search in BigQuery using theBigQueryVectorStore
class. This class is part of a set of 2 classes capable of providing a unified data storage and flexible vector search in Google Cloud:
- BigQuery Vector Search: with
BigQueryVectorStore
class, which is ideal for rapid prototyping with no infrastructure setup and batch retrieval. - Feature Store Online Store: with
VertexFSVectorStore
class, enables low-latency retrieval with manual or scheduled data sync. Perfect for production-ready user-facing GenAI applications.
Getting started
Install the library
%pip install --upgrade --quiet langchain langchain-google-vertexai "langchain-google-community[featurestore]"
To use the newly installed packages in this Jupyter runtime, you must restart the runtime. You can do this by running the cell below, which restarts the current kernel.
import IPython
app = IPython.Application.instance()
app.kernel.do_shutdown(True)
Before you begin
Set your project ID
If you don't know your project ID, try the following:
- Run
gcloud config list
. - Run
gcloud projects list
. - See the support page: Locate the project ID.
PROJECT_ID = "" # @param {type:"string"}
# Set the project id
! gcloud config set project {PROJECT_ID}
Set the region
You can also change the REGION
variable used by BigQuery. Learn more about BigQuery regions.
REGION = "us-central1" # @param {type: "string"}
Set the dataset and table names
They will be your BigQuery Vector Store.
DATASET = "my_langchain_dataset" # @param {type: "string"}
TABLE = "doc_and_vectors" # @param {type: "string"}
Authenticating your notebook environment
- If you are using Colab to run this notebook, uncomment the cell below and continue.
- If you are using Vertex AI Workbench, check out the setup instructions here.
# from google.colab import auth as google_auth
# google_auth.authenticate_user()
Demo: BigQueryVectorStore
Create an embedding class instance
You may need to enable Vertex AI API in your project by running
gcloud services enable aiplatform.googleapis.com --project {PROJECT_ID}
(replace {PROJECT_ID}
with the name of your project).
You can use any LangChain embeddings model.
from langchain_google_vertexai import VertexAIEmbeddings
embedding = VertexAIEmbeddings(
model_name="textembedding-gecko@latest", project=PROJECT_ID
)
Initialize BigQueryVectorStore
BigQuery Dataset and Table will be automatically created if they do not exist. See class definition here for all optional paremeters.
from langchain_google_community import BigQueryVectorStore
store = BigQueryVectorStore(
project_id=PROJECT_ID,
dataset_name=DATASET,
table_name=TABLE,
location=REGION,
embedding=embedding,
)
Add texts
all_texts = ["Apples and oranges", "Cars and airplanes", "Pineapple", "Train", "Banana"]
metadatas = [{"len": len(t)} for t in all_texts]
store.add_texts(all_texts, metadatas=metadatas)
Search for documents
query = "I'd like a fruit."
docs = store.similarity_search(query)
print(docs)
Search for documents by vector
query_vector = embedding.embed_query(query)
docs = store.similarity_search_by_vector(query_vector, k=2)
print(docs)
Search for documents with metadata filter
# This should only return "Banana" document.
docs = store.similarity_search_by_vector(query_vector, filter={"len": 6})
print(docs)
Batch search
BigQueryVectorStore offers a batch_search
method for scalable Vector similarity search.
results = store.batch_search(
embeddings=None, # can pass embeddings or
queries=["search_query", "search_query"], # can pass queries
)
Add text with embeddings
You can also bring your own embeddings with the add_texts_with_embeddings
method.
This is particularly useful for multimodal data which might require custom preprocessing before the embedding generation.
items = ["some text"]
embs = embedding.embed(items)
ids = store.add_texts_with_embeddings(
texts=["some text"], embs=embs, metadatas=[{"len": 1}]
)
Low-latency serving with Feature Store
You can simply use the method .to_vertex_fs_vector_store()
to get a VertexFSVectorStore object, which offers low latency for online use cases. All mandatory parameters will be automatically transferred from the existing BigQueryVectorStore class. See the class definition for all the other parameters you can use.
Moving back to BigQueryVectorStore is equivalently easy with the .to_bq_vector_store()
method.
store.to_vertex_fs_vector_store() # pass optional VertexFSVectorStore parameters as arguments