pgvector support for C++
Supports libpqxx
Run:
git clone --branch v0.2.0 https://github.com/pgvector/pgvector-cpp.git
cd pgvector-cpp
cmake -S . -B build
cmake --build build
cmake --install build # may need sudoAnd follow the instructions for your database library:
Include the header
#include <pgvector/pqxx.hpp>Enable the extension
tx.exec0("CREATE EXTENSION IF NOT EXISTS vector");Create a table
tx.exec0("CREATE TABLE items (id bigserial PRIMARY KEY, embedding vector(3))");Insert a vector
auto embedding = pgvector::Vector({1, 2, 3});
tx.exec_params("INSERT INTO items (embedding) VALUES ($1)", embedding);Get the nearest neighbors
pqxx::result R{tx.exec_params("SELECT * FROM items ORDER BY embedding <-> $1 LIMIT 5", embedding)};Retrieve a vector
auto row = tx.exec1("SELECT embedding FROM items LIMIT 1");
auto embedding = row[0].as<pgvector::Vector>();Use std::optional<pgvector::Vector> if the value could be NULL
Convert a vector to a std::vector<float>
auto float_vec = static_cast<std::vector<float>>(embedding);View the changelog
Everyone is encouraged to help improve this project. Here are a few ways you can help:
- Report bugs
- Fix bugs and submit pull requests
- Write, clarify, or fix documentation
- Suggest or add new features
To get started with development:
git clone https://github.com/pgvector/pgvector-cpp.git
cd pgvector-cpp
createdb pgvector_cpp_test
g++ -std=c++17 -Wall -Wextra -Werror -o test/pqxx test/pqxx_test.cpp -lpqxx -lpq
test/pqxx