I'm curious if there is a library or a project out there to provide a generic interface to IndexedDB or to WebSQL, depending on user's browser's support. If they're using Chrome/Safari, use WebSQL, if they're using Firefox or Internet Explorer, use IndexedDB.
The poster of this question appears to have homegrown a solution, but did not provide any source code.
JasonCasden has shared a huge list of libraries/wrappers at his presentation In-browser storage and me. Here is the list:
lawnchair
persistence.js
persistJS
amplify.store
localStorageDB
https://github.com/axemclion/IndexedDB
realStorage
YUI3 CacheOffline
dojox.storage
DomSQL
Impel
ActiveJS ActiveRecord
JazzRecord
picnet.data.DataManager
ShinyCar
lscache
Kizzy
Artemia
microcache.js
Store.js