Persistence of data in HTML5

Question

Can anybody tell me about the DATA PERSISTENCE in

1. HTML5 Web SQL Database
2. Local Storage
3. Session Storage

Also please tell me how will clearing the cache memory affect them.

Answer 1

Has all the info you need : http://www.html5rocks.com/en/features/offline

Answer 2

1. HTML5 Web SQL seems to be abandoned, so I won't bother with that.
2. Local storage persists "forever" i.e. Until the application or the user explicitly clears the data.
3. Session storage persists only until the end of browser session(Some browsers persist the data over a crash situation)

Clearing the cache should have no effect on the saved data, but clearing the cookies might destroy it.