Apache AsterixDB vs PouchDB

Apache AsterixDB is a free, open source, self-managed Big Data Management System for ingesting, storing, indexing, querying and analyzing data. Its Asterix Data Model extends JSON with object-database concepts, while SQL++ and AQL provide declarative queries for semistructured information. Partitioned LSM-based storage supports B+ tree, R-tree and inverted keyword secondary indexes. External datasets can be queried without loading everything into AsterixDB, using adapters for HDFS and local filesystems. Continuous feeds can ingest sources such as Twitter, RSS and sockets. The HTTP query API accepts SQL++ and can return immediate, deferred or asynchronous results. Installation options include NCService, Ansible and Amazon Web Services. The Hyracks parallel runtime has been scale-tested on up to 1000+ cores and 500+ disks. Documentation describes basic transactional concurrency and recovery, and identifies web data warehousing and social data analysis as suitable uses.

PouchDB is a free, open-source JavaScript database for storing application data locally and synchronizing it with CouchDB and compatible servers. It keeps data available offline and can sync local and remote databases after a connection returns. Its replication API can follow later changes and retry after connection failures when configured. PouchDB runs in browsers and Node.js, as well as Cordova, PhoneGap, NW.js, Electron, and Chrome apps. Browser storage defaults to IndexedDB, while Node.js defaults to LevelDB. Documents can include image or audio attachments stored as base64 data or Blobs. PouchDB includes a map/reduce API; Mango queries require the separate pouchdb-find plugin. Its asynchronous API supports callbacks, promises, and async functions, and the project names Angular, React, Ember, and Backbone as framework examples. Listed compatible servers include CouchDB 1.x, 2.x, and 3.x, Cloudant, and PouchDB Server. Replication requires a backend that speaks the CouchDB replication protocol. The project homepage says Apache PouchDB is undergoing incubation at the Apache Software Foundation.