Supabase (Postgres)
Supabase is an open-source Firebase alternative.
Supabase
is built on top ofPostgreSQL
, which offers strong SQL querying capabilities and enables a simple interface with already-existing tools and frameworks.
PostgreSQL also known as
Postgres
, is a free and open-source relational database management system (RDBMS) emphasizing extensibility and SQL compliance.
This notebook shows how to use Supabase
and pgvector
as your VectorStore.
You'll need to install langchain-community
with pip install -qU langchain-community
to use this integration
To run this notebook, please ensure:
- the
pgvector
extension is enabled - you have installed the
supabase-py
package - that you have created a
match_documents
function in your database - that you have a
documents
table in yourpublic
schema similar to the one below.
The following function determines cosine similarity, but you can adjust to your needs.
-- Enable the pgvector extension to work with embedding vectors
create extension if not exists vector;
-- Create a table to store your documents
create table
documents (
id uuid primary key,
content text, -- corresponds to Document.pageContent
metadata jsonb, -- corresponds to Document.metadata
embedding vector (1536) -- 1536 works for OpenAI embeddings, change if needed
);
-- Create a function to search for documents
create function match_documents (
query_embedding vector (1536),
filter jsonb default '{}'
) returns table (
id uuid,
content text,
metadata jsonb,
similarity float
) language plpgsql as $$
#variable_conflict use_column
begin
return query
select
id,
content,
metadata,
1 - (documents.embedding <=> query_embedding) as similarity
from documents
where metadata @> filter
order by documents.embedding <=> query_embedding;
end;
$$;
# with pip
%pip install --upgrade --quiet supabase
# with conda
# !conda install -c conda-forge supabase
We want to use OpenAIEmbeddings
so we have to get the OpenAI API Key.
import getpass
import os
if "OPENAI_API_KEY" not in os.environ:
os.environ["OPENAI_API_KEY"] = getpass.getpass("OpenAI API Key:")
if "SUPABASE_URL" not in os.environ:
os.environ["SUPABASE_URL"] = getpass.getpass("Supabase URL:")
if "SUPABASE_SERVICE_KEY" not in os.environ:
os.environ["SUPABASE_SERVICE_KEY"] = getpass.getpass("Supabase Service Key:")
# If you're storing your Supabase and OpenAI API keys in a .env file, you can load them with dotenv
from dotenv import load_dotenv
load_dotenv()
First we'll create a Supabase client and instantiate a OpenAI embeddings class.
import os
from langchain_community.vectorstores import SupabaseVectorStore
from langchain_openai import OpenAIEmbeddings
from supabase.client import Client, create_client
supabase_url = os.environ.get("SUPABASE_URL")
supabase_key = os.environ.get("SUPABASE_SERVICE_KEY")
supabase: Client = create_client(supabase_url, supabase_key)
embeddings = OpenAIEmbeddings()
Next we'll load and parse some data for our vector store (skip if you already have documents with embeddings stored in your DB).
from langchain_community.document_loaders import TextLoader
from langchain_text_splitters import CharacterTextSplitter
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)
Insert the above documents into the database. Embeddings will automatically be generated for each document. You can adjust the chunk_size based on the amount of documents you have. The default is 500 but lowering it may be necessary.
vector_store = SupabaseVectorStore.from_documents(
docs,
embeddings,
client=supabase,
table_name="documents",
query_name="match_documents",
chunk_size=500,
)
Alternatively if you already have documents with embeddings in your database, simply instantiate a new SupabaseVectorStore
directly:
vector_store = SupabaseVectorStore(
embedding=embeddings,
client=supabase,
table_name="documents",
query_name="match_documents",
)
Finally, test it out by performing a similarity search:
query = "What did the president say about Ketanji Brown Jackson"
matched_docs = vector_store.similarity_search(query)
print(matched_docs[0].page_content)
Tonight. I call on the Senate to: Pass the Freedom to Vote Act. Pass the John Lewis Voting Rights Act. And while you’re at it, pass the Disclose Act so Americans can know who is funding our elections.
Tonight, I’d like to honor someone who has dedicated his life to serve this country: Justice Stephen Breyer—an Army veteran, Constitutional scholar, and retiring Justice of the United States Supreme Court. Justice Breyer, thank you for your service.
One of the most serious constitutional responsibilities a President has is nominating someone to serve on the United States Supreme Court.
And I did that 4 days ago, when I nominated Circuit Court of Appeals Judge Ketanji Brown Jackson. One of our nation’s top legal minds, who will continue Justice Breyer’s legacy of excellence.