Ionic 2 storage module clarification - sqlite

Question

There is a lot of confusion when it comes to ionic 2 storage. There was a lot of changes in the new ionic version as Storage was moved to #ionic/strage . I am new to Ionic so some of the things are confusing for me. I have web-development background. From the documentation,
A simple key-value Storage module for Ionic apps based on LocalForage,
with out-of-the-box support for SQLite. This utility makes it easy to
use the best storage engine available without having to interact with
it directly. Currently the ordering is SQLite, IndexedDB, WebSQL, and
LocalStorage.
Installation
npm install #ionic/storage
If you'd like to use SQLite as a storage engine, install a SQLite plugin (only works while running in a simulator or on device):
cordova plugin add cordova-sqlite-storage --save
What I would like to know is, what happens when I run this in browser ? Where does it store the data? What would happen if I dont use cordova-sqlite-storage ? Where does it store the data then?
Ionic also supports SQLite plugin natively to store data in SQLite database .
import { SQLite } from 'ionic-native'
How is it different from Storage other than the fact that there is a fallback to IndexedDB, WebSQL, and LocalStorage ?
I hope my thoughts are in the right direction. A clear answer on how these modules work would be really helpful.

Answer 1

Ionic Storage is the first module written with proper web fallback in mind.
One near-term goal we have with Ionic is enabling devs to build 99% of their app in the browser. It's a much faster workflow. This means support for native plugins that have web fallbacks, as well as better mocking for ones that don't. - Max Lynch on Twitter
By default when running, #ionic/storage will prioritize the storage methods this way:
When running in a native app context, Storage will prioritize using
SQLite, as it's one of the most stable and widely used file-based
databases, and avoids some of the pitfalls of things like localstorage
and IndexedDB, such as the OS deciding to clear out such data in low
disk-space situations.
When running in the web or as a Progressive Web App, Storage will attempt to use IndexedDB, WebSQL, and localstorage, in that order.
- Official Documentation
So when your app is running in the browser (or on a device without the SQLite plugin) it will detect that SQLite is not available and will use IndexedDB/WebSQL instead.
How is it different from Storage other than the fact that there is a fallback to IndexedDB, WebSQL, and LocalStorage?
The SQLite plugin gives you low-level access to an SQLite database, which means you have to care about creating/updating your schemas, and write queries.
#ionic/storage is a wrapper which abstract away the differences of LocalForge and SQLite and provide a simple, unified API to store key/value pairs.
Also it takes care of serializing/deserializing of your objects.

Answer 2

From my understanding of the Ionic 2 RC Storage module, when you are running in the browser you are now only able to store key-value pairs (LocalStorage). You are currently not able to store anything more than that, so you should check out other options like PouchDB and LocalForage if you need full SQL support. This definitely isn't ideal for progressive web apps.