TiDB - Distributed NewSQL database compatible with MySQL protocol

•    Go

TiDB is a distributed SQL database. Inspired by the design of Google F1 and Google Spanner, TiDB supports the best features of both traditional RDBMS and NoSQL. It is horizontally scalable, grow TiDB as your business grows. You can increase the capacity simply by adding more machines.

YugaByte Database - Transactional, high-performance database for building internet-scale, globally-distributed applications

•    C++

A cloud-native database for building mission-critical applications. This repository contains the Community Edition of the YugaByte Database.YugaByte offers both SQL and NoSQL in a single, unified db. It is meant to be a system-of-record/authoritative database that applications can rely on for correctness and availability. It allows applications to easily scale up and scale down in the cloud, on-premises or across hybrid environments without creating operational complexity or increasing the risk of outages.

CockroachDB - Cloud-native SQL database.

•    Go

CockroachDB is a cloud-native SQL database for building global, scalable cloud services that survive disasters.CockroachDB is a distributed SQL database built on a transactional and strongly-consistent key-value store. It scales horizontally; survives disk, machine, rack, and even datacenter failures with minimal latency disruption and no manual intervention; supports strongly-consistent ACID transactions; and provides a familiar SQL API for structuring, manipulating, and querying data.

Apache Trafodion - Webscale SQL-on-Hadoop solution enabling transactional or operational workloads on Apache Hadoop.

•    C++

Apache Trafodion is a webscale SQL-on-Hadoop solution enabling transactional or operational workloads on Apache Hadoop. Trafodion builds on the scalability, elasticity, and flexibility of Hadoop. Trafodion extends Hadoop to provide guaranteed transactional integrity, enabling new kinds of big data applications to run on Hadoop.

memdb - Distributed Transactional In-Memory Database (全球首个支持分布式事务的MongoDB)

•    Javascript

Copy default config file from node_modules/memdb-server/memdb.conf.js to ~/.memdb/ (mkdir if not exist), and modify it on your need. Please read comments carefully. See the video bellow, note how ACID transaction work cross multiple shards.

QuestDB - Fast relational time-series database

•    Java

QuestDB is an open-source NewSQL relational database designed to process time-series data, faster. QuestDB ingests data via HTTP, PostgresSQL wire protocol, Influx line protocol or directly from Java. Reading data is done using SQL via HTTP, PostgreSQL wire protocol or via Java API. The whole database and console fits in a 3.5Mb package.

BigchainDB - The Scalable Blockchain Database

•    Python

BigchainDB allows developers and enterprise to deploy blockchain proof-of-concepts, platforms and applications with a scalable blockchain database, supporting a wide range of industries and use cases. It is a decentralization ecosystem: a decentralized database, at scale. It can perform 1 million writes per second throughput, store petabytes of data, and sub-second latency.

rqlite - The lightweight, distributed relational database built on SQLite.

•    Go

rqlite is a distributed relational database, which uses SQLite as its storage engine. rqlite uses Raft to achieve consensus across all the instances of the SQLite databases, ensuring that every change made to the system is made to a quorum of SQLite databases, or none at all. It also gracefully handles leader elections, and tolerates failures of machines, including the leader. rqlite is available for Linux, OSX, and Microsoft Windows.rqlite gives you the functionality of a rock solid, fault-tolerant, replicated relational database, but with very easy installation, deployment, and operation. With it you've got a lightweight and reliable distributed relational data store. Think etcd or Consul, but with relational data modelling also available.

agensgraph - AgensGraph, a transactional graph database based on PostgreSQL

•    C

AgensGraph is a new generation multi-model graph database for the modern complex data environment. AgensGraph is a multi-model database, which supports the relational and graph data model at the same time that enables developers to integrate the legacy relational data model and the flexible graph data model in one database. AgensGraph supports ANSI-SQL and openCypher (http://www.opencypher.org). SQL queries and Cypher queries can be integrated into a single query in AgensGraph. AgensGraph is based on the powerful PostgreSQL RDBMS, and is very robust, fully-featured and ready for enterprise use. AgensGraph is optimized for handling complex connected graph data and provides plenty of powerful database features essential to the enterprise database environment including ACID transactions, multi-version concurrency control, stored procedure, triggers, constraints, sophisticated monitoring and a flexible data model (JSON). Moreover, AgensGraph leverages the rich eco-systems of PostgreSQL and can be extended with many outstanding external modules, like PostGIS.

Bedrock - Rock solid distributed database specializing in active/active automatic failover and WAN replication

•    C

Bedrock is a simple, modular, WAN-replicated, Blockchain-based data foundation for global-scale applications. Bedrock was built by Expensify, and is a networking and distributed transaction layer built atop SQLite, the fastest, most reliable, and most widely distributed database in the world. Bedrock is Blockchain-based. This means it uses a private blockchain to synchronize and self organize.

Nebula Graph - A distributed, scalable, lightning-fast graph database

•    C++

Nebula Graph is an open-source graph database capable of hosting super large-scale graphs with billions of vertices (nodes) and trillions of edges, with milliseconds of latency. It delivers enterprise-grade high performance to simplify the most complex data sets imaginable into meaningful and useful information.

catena - Catena is a distributed database based on a blockchain, accessible using SQL.

•    Swift

Catena is a distributed database based on a blockchain, accessible using SQL. Catena timestamps database transactions (SQL) in a decentralized way between nodes that do not or cannot trust each other, while enforcing modification permissions ('grants') that were agreed upon earlier. A Catena blockchain contains SQL transactions that, when executed in order, lead to the agreed-upon state of the database. The transactions are automatically replicated to, validated by, and replayed on participating clients. A Catena database can be connected to by client applications using the PostgreSQL wire protocol (pq).

orbit-db - Peer-to-Peer Databases for the Decentralized Web

•    Javascript

OrbitDB is a serverless, distributed, peer-to-peer database. OrbitDB uses IPFS as its data storage and IPFS Pubsub to automatically sync databases with peers. It's an eventually consistent database that uses CRDTs for conflict-free database merges making OrbitDB an excellent choice for decentralized apps (dApps), blockchain applications and offline-first web applications. All databases are implemented on top of ipfs-log, an immutable, operation-based conflict-free replicated data structure (CRDT) for distributed systems. If none of the OrbitDB database types match your needs and/or you need case-specific functionality, you can easily implement and use a custom database store of your own.

Lindb - Distributed Time Series Database

•    Go

LinDB is an open-source Time Series Database which provides high performance, high availability and horizontal scalability. LinDB takes a lot of best practice of TSDB and implements some optimizations based on the characteristics of time series data. Unlike writing a lot of Continuous-Query for InfluxDB, LinDB supports rollup in specific interval automatically after creating the database. Moreover, LinDB is extremely fast for parallel querying and computing of distributed time series data.

Cassandra - Scalable Distributed Database

•    Java

The Apache Cassandra Project develops a highly scalable second-generation distributed database, bringing together Dynamo's fully distributed design and Bigtable's ColumnFamily-based data model. Cassandra is suitable for applications that can't afford to lose data. Data is automatically replicated to multiple nodes for fault-tolerance.

tidis - Distributed transactional NoSQL database, Redis protocol compatible using tikv as backend

•    Go

Tidis is a Distributed NoSQL database, providing a Redis protocol API (string, list, hash, set, sorted set), written in Go. Tidis is like TiDB layer, providing protocol transform and data structure compute, powered by TiKV backend distributed storage which use Raft for data replication and 2PC for distributed transaction.

Bagri - XML/Document DB on top of distributed cache

•    Java

Bagri is a Document Database built on top of distributed cache solution like Hazelcast or Coherence. The system allows to process semi-structured schema-less documents and perform distributed queries on them in real-time. It scales horizontally very well with use of data sharding, when all documents are distributed evenly between distributed cache partitions.

PostgreSQL - Powerful, Open Source Object-Relational Database System

•    C

PostgreSQL is a powerful, open source object-relational database system. It has more than 15 years of active development and a proven architecture that has earned it a strong reputation for reliability, data integrity, and correctness. It is fully ACID compliant, has full support for foreign keys, joins, views, triggers, and stored procedures (in multiple languages). It has native programming interfaces for most of the programming language.

SchemaCrawler

SchemaCrawler is an open-source Java API that makes working with database metadata as easy as working with plain old Java objects. SchemaCrawler is also a database schema discovery and comprehension, and schema documentation tool. You can search for database schema objects using regular expressions, and output the schema and data in a readable text format, and find potential design issues with lint . The output is designed to be diff-ed against other database schemas. SchemaCrawler support

LEAP RDBMS

•    C

LEAP is an RDBMS (Relational Database Management System) implementing the relational Algebra - a core part of relational database theory. It is primarily used as an educational tool, but has found some novel uses and applications.