Free HarperDB Alternatives

TimescaleDB is a leading open-source relational database for time-series data. The database is provided as fully managed or self‑hosted software, giving the power of choice back to developers and organizations. Timescale gives you all the reliability and flexibility of PostgreSQL. It allows you to use regular SQL to construct queries to better understand your products and your users. While achieve 10-100x faster queries than PostgreSQL, InfluxDB, and MongoDB with native optimizations for time-series.

OpenTSDB is a free and open-source distributed, scalable Time Series Database written on top of Apache HBase. OpenTSDB was designed to address a common need: store, index and serve metrics collected from computer systems such as network gear, operating systems and applications, at a large scale, and make this data easily accessible and graphable. OpenTSDB allows you to collect thousands of metrics from tens of thousands of hosts and applications, at a high rate and will never delete or downsample data and can easily store hundreds of billions of data points.

VoltDB is a blazingly fast NewSQL database management system that is specifically designed to run on modern scale-out architectures - fast, inexpensive servers connected via high-speed data networks. VoltDB is a popular choice for companies with high data throughput requirements, like in the telecommunications industry. 5G has changed the game for telcos, and new rules call for a new way of managing data. VoltDB is built for today’s massive data volume and complexity, allowing businesses to survive and thrive in the age of 5G, IoT, and whatever comes next.

solidDB is a fully featured, relational in-memory database that meets the performance and reliability demands of real-time applications. There are currently millions of deployments utilizing the power of SolidDB for telecommunications networks, enterprise applications, and embedded software & systems. Market leaders such as Cisco, HP, Alcatel, Nokia and Siemens rely on solidDB for their mission-critical applications.

PouchDB is a free and open-source JavaScript database inspired by Apache CouchDB. The database is designed from the ground-up to run well within modern web browsers. With PouchDB you can create web applications that works as well offline as they do online. PouchDB achives this by storing data locally, then synchronize it with CouchDB and compatible servers when the user get internet access once again. This is especially useful for applications facing countries and regions with lower quality internet connections or unstable infrastructure.

A Chinese developed open-source NewSQL database that supports analytical processing and hybrid transactional workloads. TiDB is licensed under the Apache 2.0 license and primarily developed by PingCAP, Inc. The database provides high availability with strong consistency and horizontal scaling and is compatible with MySQL.

KeyDB is fast, free, and open-source NoSQL database with full compatibility for Redis APIs, clients, and modules. The database was originally forked from the Redis code-base and has been improved to handle multithreading, memory efficiency, and higher throughput. KeyDB is now a fully multithreaded and allow many machine cores to operate a single node resulting in 5X the throughput of Redis (v5) and up to 3x the throughput of Redis (v6). KeyDB also includes Redis Enterprise such as Active Replication, FLASH storage support, and other features like direct backup to AWS S3.

CouchDB is a free and open-source document-oriented NoSQL database developed by the Apache Foundation. The database is written and implemented in the language Erlang and provides the use of multiple formats and protocols to store, transfer, and process data. With CouchDB you query data with JavaScript using MapReduce, and HTTP for an API. Which can be done across multiple distributed CouchDB instances as the database has the ability to synchronize multiple copies of the same database, across servers.

QuestDB is a relational column-oriented time series database designed for real-time analytics on time series and event data. It uses the SQL language and include extensions for time series data. QuestDB is released as free and open source software and distributed as a single binary including a trimmed version of the JVM (Java Virtual Machine) weighing in at only 24.5 MB.

Cockroach is a distributed key/value datastore that allow you to build, scale and manage modern, data-intensive applications. The database delivers distributed SQL by combining the familiarity of relational data with limitless, elastic cloud scale and bulletproof resilience. Correct data is a must for mission-critical and even the most common applications. CockroachDB provides guaranteed ACID compliant transactions, allowing you to fully trust your data.

MonetDB is an column-oriented database management system developed at the Centrum Wiskunde & Informatica. The database is released as free and open source software under the Mozilla Public License 2.0. By design, MonetDB can handle high performance on complex queries against large databases with hundreds of columns and millions of rows.

CrateDB is the leading, distributed SQL database for relational and time‑series data. CrateDB provides a distributed SQL DBMS built atop NoSQL storage & indexing delivers the best of SQL & NoSQL in one DB. It's designed for simple scalability with a masterless architecture with auto-sharding & replication. It also provides solutions for dynamic schema where the schema evolves automatically as new columns are inserted, while handling any tabular or non-tabular data to support a wide range of use cases. CrateDB is the perfect choice for your machine data.