SurrealDB

vs

TimescaleDB

Supabase is a free and open-source self-hosted and SaaS provided alternative to Firebase. With Supabase you can add a realtime REST API to a PostgreSQL without writing a single line of code.

Fauna is the data API for client-serverless applications. It provides web-native GraphQL interface, with support for custom business logic and integration with the serverless ecosystem. Fauna transforms the traditional DBMS into a Data API that gives you all of the capabilities of traditional database, without sacrificing flexibility, scale, and performance. By utilizing a globally-distributed storage and compute fabric, Fauna-powered applications are delivered to end-users fast and reliably on modern security infrastructure.

EdgeDB is a database designed on top of Postgres with the goal of eliminating some of the shortcommings of relation and NoSQL databases.  At first glance, EdgeDB looks like a regular object relational mapper (ORM), however it's far more than that, It's a full-fledged database with a formally-defined query language, a migrations system, a suite of client libraries in different languages, a command line tool, and a soon comming cloud hosting platform. The goal of EdgeDB has been to rethink every aspect of how developers model, migrate, manage, and query their database.

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.

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.

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.