pgvector-erlang

Category: SDKs & Libraries
Brand: pgvector
Repository: https://github.com/pgvector/pgvector-erlang

Erlang client examples for the pgvector PostgreSQL extension, demonstrating how to run vector operations from Erlang systems using epgsql.

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Features

• Erlang examples for pgvector

  • Shows how to integrate the pgvector extension with Erlang applications.
  • Focused around the epgsql PostgreSQL driver.

• epgsql support

  • Uses epgsql:equery/3 for executing SQL commands from Erlang.
  • Compatible with databases where the pgvector extension is installed.

• Extension setup

  • Example for enabling the pgvector extension:
    • CREATE EXTENSION IF NOT EXISTS vector

• Schema definition for vector data

  • Example of creating a table with vector columns:
    • CREATE TABLE items (id bigserial PRIMARY KEY, embedding vector(3))

• Vector insertion

  • Demonstrates inserting vector data into PostgreSQL from Erlang:
    • INSERT INTO items (embedding) VALUES ($1), ($2) with vector values like [1,2,3].

• Nearest neighbor queries

  • Example query to retrieve nearest neighbors by distance:
    • SELECT id FROM items ORDER BY embedding <-> $1 LIMIT 5
  • Uses the <-> operator for distance-based ordering.

• Approximate nearest neighbor indexing

  • Examples of creating approximate indexes for faster search:
    • HNSW index: CREATE INDEX ON items USING hnsw (embedding vector_l2_ops)
    • IVFFlat index: CREATE INDEX ON items USING ivfflat (embedding vector_l2_ops) WITH (lists = 100)

• Multiple distance metrics

  • Support for different operator classes via configuration in SQL:
    • vector_l2_ops – L2 (Euclidean) distance
    • vector_ip_ops – inner product
    • vector_cosine_ops – cosine distance

• Example project setup for development

  • Steps shown in the repo for running the example:
    • Clone repository
    • Create test database pgvector_erlang_test
    • Build with rebar3 escriptize
    • Run example script from _build/default/bin/example
  • Full example available in src/example.erl.

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Integration

• Primary driver: epgsql (Erlang PostgreSQL driver)
• Database: PostgreSQL with pgvector extension enabled

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Pricing

• Not specified in the provided content. The project appears to be an open-source library hosted on GitHub.