Best way to use JSON as a database?

I am creating an offline mobile web app, and am looking at using JSON to replicate some of my database tables and storing that in localStorage. (I am aware of Web SQL Database but it doesn't look particularly future-proof.)

I started with a very basic JSON output from the database, which looks a bit like this:

{
  "1": {"id":"1","name":"Hello","alias":"hello","category":"8"},
  "2": {"id":"2","name":"World","alias":"world","category":"3"},
  ...
}

However, there is a lot of data in many tables and space could be an issue with the constant repeating of field names. Storing the data like this halves the size:

{
  "1": ["1","Hello","hello","8"},
  "2": ["2","World","world","3"},
  ...
}

But now I have to reference a piece of data with a numeric index, possibly filling my code with magic numbers. I thought of storing an array like ["id","name"...]开发者_开发百科 in another variable but the extra lookups seem like they would get messy.

Are there any practical ways to avoid that, but also keeping the Javascript code fairly neat? Any other useful strategies for this kind of development?

would it be possible to convert it into a format like this:

{
   id:{1:1, 2:2, ...},
   name:{1:hello, 2:world},
   alias:{1:hello, 2:world},
   category{1:8,2:3}
}

This way, you only store each column once, but you can still easily find things by their id.

JSON is not a database. JSON is a data interchange format.

Not sure if it would work across all mobile platforms, but XML would be an option.