A fast, low memory, transactional, index & query enabled NoSQL database engine and server for Node.js with realtime data change notifications. Can be used as a standalone local database, or to connect to remote databases. Is able to synchronize with a server and other clients in realtime, and upon reconnect after having been used offline. Great free and open source Firebase alternative.
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Pros
Pro Also runs in the browser
Besides having a client that connects to a remote AceBase server, the database itself is able to run in the browser. It uses the same to codebase with a different storage provider (IndexedDB instead of binary in Node.js), which makes it possible to run a fullblown realtime database in the browser that syncs between multiple tabs, and can additionally be used as local cache database for an AceBase client to enable offline usage.
Pro Synchronizes very well
Realtime data change notifications are blazingly fast which makes synchronization between apps instant and effortless. When used offline, local and remote changes are synchronized upon reconnect without any hassles. Changes are logged on the property level which makes them synchronize extremely efficient and fast.
Pro Very easy to setup
It takes very little effort to add AceBase to a Node.js or web project, it's ready to use after installing it as a dependency. It uses a API very similar to that of the Firebase realtime database, which makes it familiar and easy to migrate from Firebase to AceBase for a local db instance or fullblown realtime db server.
Cons
Con Only has Javascript SDK
There currently are no other SDKs besides the Javascript client, which limits its usage to Node.js / Electron / Web environments only. However, the project is fully open-source and the server has a REST API, so most database operations can also be performed using http requests. The latter also makes it possible for the community to develop their own client SDKs.