pghashlib is a PostgreSQL extension providing high-performance hash functions for data processing and analysis. Currently includes MurmurHash3, CRC32, CityHash64, CityHash128, SipHash-2-4, SpookyHash, xxHash32, xxHash64, FarmHash32, FarmHash64, HighwayHash64, HighwayHash128, HighwayHash256, MetroHash64, MetroHash128, t1ha0, t1ha1, t1ha2, t1ha2_128, WyHash, lookup2, lookup3be, and lookup3le algorithms.

1. Installation
2. Quick Start
3. Supported Functions
4. Documentation
5. Compatibility
6. Contributing
7. License

git clone https://github.com/christyjacob4/pghashlib.git
cd pghashlib
make
make install # may need sudo

Make sure you have PostgreSQL development headers installed:

• Ubuntu/Debian: sudo apt-get install postgresql-server-dev-all
• CentOS/RHEL/Fedora: sudo yum install postgresql-devel
• macOS: brew install postgresql

docker compose up -d --build
docker compose exec postgres psql -U postgres -c "CREATE EXTENSION hashlib;"

CREATE EXTENSION hashlib;

-- Basic usage examples
SELECT murmurhash3_32('hello world');
SELECT cityhash64('hello world');
SELECT wyhash('hello world');

-- With custom seeds
SELECT murmurhash3_32('hello world', 42);
SELECT xxhash64('hello world', 12345);

-- Common use cases
-- Data partitioning
SELECT abs(cityhash64(user_id::text)) % 8 AS partition FROM users;

-- Random sampling (10%)
SELECT * FROM large_table WHERE murmurhash3_32(id::text) % 100 < 10;

• Getting Started Guide - Learn how to use hash functions with practical examples and common use cases
• Algorithm Reference - Complete documentation for all hash functions with detailed examples

• PostgreSQL Versions: 12, 13, 14, 15, 16, 17
• Operating Systems: Linux, macOS, Windows (via WSL)
• Architectures: x86_64, ARM64

We welcome contributions! Please see our Contributing Guide for detailed information on development setup, testing, and contribution guidelines.

This project is licensed under the PostgreSQL License - see the LICENSE file for details.