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For the complete documentation index for agents and LLMs, see llms.txt.

SupabasePgvectorEmbeddingRetriever

Retrieve documents from a SupabasePgvectorDocumentStore based on dense embedding similarity. This component is a thin wrapper around PgvectorEmbeddingRetriever adapted for use with Supabase.

Embedding Models in Pipelines and Indexes

The embedding model you use to embed documents in your index must be the same as the embedding model you use to embed the query in your pipeline.

This means the embedders for your indexes and pipelines must match. For example, if you use CohereDocumentEmbedder to embed your documents, you should use CohereTextEmbedder with the same model to embed your queries.

Key Features​

  • Performs dense vector similarity search against a Supabase PostgreSQL database with pgvector.
  • Supports cosine_similarity, inner_product, and l2_distance vector functions.
  • Reads the connection string from the SUPABASE_DB_URL environment variable by default.
  • Compatible with HNSW index search strategy for performance at scale.
  • Configurable filter policy to merge or replace filters at query time.

Configuration​

  1. Drag the SupabasePgvectorEmbeddingRetriever component onto the canvas from the Component Library.
  2. Click on the component to open the configuration panel.
  3. Configure the nested SupabasePgvectorDocumentStore:
    • Set connection_string as a secret called SUPABASE_DB_URL. The connection string format is postgresql://postgres.[project-ref]:[password]@aws-0-[region].pooler.supabase.com:5432/postgres. For instructions, see Add Secrets.
    • Use session mode (port 5432) or a direct connection for best compatibility with pgvector.
  4. Connect a text embedder to provide query_embedding as input.

Connections​

SupabasePgvectorEmbeddingRetriever receives a query_embedding (list of floats) from a text embedder such as SentenceTransformersTextEmbedder. It outputs a list of Document objects you can connect to PromptBuilder or other downstream components.

Source Code​

To check this component's source code, open embedding_retriever.py in the Haystack Core Integrations repository.

Usage Examples​

Basic Configuration​

SupabasePgvectorEmbeddingRetriever:
type: haystack_integrations.components.retrievers.supabase.embedding_retriever.SupabasePgvectorEmbeddingRetriever
init_parameters:
document_store:
type: haystack_integrations.document_stores.supabase.document_store.SupabasePgvectorDocumentStore
init_parameters:
connection_string:
type: env_var
env_vars:
- SUPABASE_DB_URL
strict: false
embedding_dimension: 384
top_k: 10

Using the Component in a Pipeline​

# haystack-pipeline
components:
text_embedder:
type: haystack_integrations.components.embedders.sentence_transformers.SentenceTransformersTextEmbedder
init_parameters:
model: sentence-transformers/all-MiniLM-L6-v2

document_store:
type: haystack_integrations.document_stores.supabase.document_store.SupabasePgvectorDocumentStore
init_parameters:
connection_string:
type: env_var
env_vars:
- SUPABASE_DB_URL
strict: false
embedding_dimension: 384
vector_function: cosine_similarity

retriever:
type: haystack_integrations.components.retrievers.supabase.embedding_retriever.SupabasePgvectorEmbeddingRetriever
init_parameters:
document_store: document_store
top_k: 5
vector_function: cosine_similarity

connections:
- sender: text_embedder.embedding
receiver: retriever.query_embedding

inputs:
query:
- text_embedder.text

outputs:
documents: retriever.documents

Parameters​

Inputs​

ParameterTypeDescription
query_embeddingList[float]The query embedding vector to search for similar documents.
filtersOptional[Dict[str, Any]]Filters to apply at query time.
top_kOptional[int]Maximum number of documents to retrieve. Overrides the init-time value.

Outputs​

ParameterTypeDescription
documentsList[Document]A list of the most similar documents from the document store.

Init Parameters​

These are the parameters you can configure in Pipeline Builder:

ParameterTypeDefaultDescription
document_storeSupabasePgvectorDocumentStoreThe Supabase pgvector document store to retrieve documents from.
filtersOptional[Dict[str, Any]]NoneDefault filters applied to all searches.
top_kint10Maximum number of documents to return.
vector_functionOptional[Literal["cosine_similarity", "inner_product", "l2_distance"]]NoneThe similarity function to use. Defaults to the one set in the document store. When using HNSW search strategy, this should match the function used during index creation.
filter_policyFilterPolicyFilterPolicy.REPLACEHow to handle filters passed at query time. REPLACE replaces init-time filters; MERGE combines them.

Run Method Parameters​

These are the parameters you can configure for the component's run() method. This means you can pass these parameters at query time through the API, in Playground, or when running a job. For details, see Modify Pipeline Parameters at Query Time.

ParameterTypeDefaultDescription
query_embeddingList[float]The embedding vector to search with.
filtersOptional[Dict[str, Any]]NoneRuntime filters to apply.
top_kOptional[int]NoneMaximum number of documents to retrieve. Overrides the init-time value.