Research alternatives to LevelDB supporting range queries

[jacoscaz]

Goal

Add support for range-based queries.

Check out

• [x] http://taffydb.com
• [x] https://github.com/kripken/sql.js/
• [x] https://github.com/agershun/alasql
• [x] https://github.com/louischatriot/nedb
• [x] https://github.com/pouchdb/pouchdb

Notes

• TaffyDB
  • last commit in 2018
• sql.js
  • doesn't persist changes unless one dumps to a TypedArray
• alasql
  • last publish on NPM dated 16 days
  • 6k+ weekly downloads
• nedb
  • last publish on NPM dated 4 years ago
  • 40k+ weekly downloads
• PouchDB
  • works both locally and remotely, can sync with remote counterpart
  • JavaScript implementation of CouchDB's API
  • 14k+ weekly downloads
  • can use indexeddb and leveldb as backends

Dynamic indexes

• In addition to switching to a different backend, a potential alternative would be to bring back dynamic indexes and implement a query engine that integrates index scans and in-memory strategies to compute responses to queries based on which indexes are currently registered on a given instance of quadstore.
• Worth mentioning that Jena + TBD only uses 3 indexes more than quadstore: GOSP, GPOS, GSPO, OSPG, SPOG, POSG, SPO, POS, OSP.
• Quadstore could throw errors on range queries that cannot be run with current indexes.

[jacoscaz]

Working on experimental indexing in https://github.com/beautifulinteractions/node-quadstore/tree/feature/experimental-indexing

[jacoscaz]

Confirmed - will maintain current backend based on levelup and merge in support for configurable indexes as implemented in https://github.com/beautifulinteractions/node-quadstore/tree/feature/experimental-indexing