Electron app with database

SQLite is a good option for a local database that you can ship with your application. It won't require the user to setup or install any extra dependencies. It's certainly not as full featured as a full on server, but it should be good enough for a local desktop app.

There are many standalone databases you can use with JavaScript and Electron applications. Here are some that I can recommend

https://github.com/louischatriot/nedb (last release 4 years ago)

https://github.com/pubkey/rxdb (many features, observable queries)

https://github.com/pouchdb/pouchdb (many open issues)

https://github.com/techfort/LokiJS (only in-memory storage)

https://github.com/typicode/lowdb (good for simple, small datasets)