How to make a local offline database

I'm about 3 years late in answering this, but considering that there was no actual discussion on the available options at the time, and that the database that OP ended up choosing is now deprecated, I figured i'd throw in my two cents on the matter.

First, one needs to consider whether one actually needs a client-side database. More specifically...

• Do you need explicit or implicit relationships between your data items?
• How about the ability to query over said items?
• Or more than 5 MB in space?

If you answered "no" to all of the above, go with localStorage and save yourself from the headaches that are the WebSQL and IndexedDB APIs. Well, maybe just the latter headache, since the former has, as previously mentioned , been deprecated.

Otherwise, IndexedDB is the only option as far as native client-side databases go, given it is the only one that remains on the W3C standards track.

Check out BakedGoods if you want to utilize any of these facilities, and more, without having to write low-level storage operation code. With it, placing data in the first encountered native database which is supported on a client, for example, is as simple as:

bakedGoods.set({    data: [{key: "key1", value: "val1"}, {key: "key2", value: "val2"}],    storageTypes: ["indexedDB", "webSQL"],    //Will be polyfilled with defaults for equivalent database structures    optionsObj: {conductDisjointly: false},    complete: function(byStorageTypeStoredKeysObj, byStorageTypeErrorObj){}});

Oh, and for the sake of complete transparency, BakedGoods is maintained by this guy right here :) .