relationship in json data vs actual relationship in db

Question

I thought I know but later on I stuck and became confused. I want to ask is it possible to 'think relationship' in json or it can be done only when u are designing your backend?

Answer 1

JSON doesn't support object references, but JavaScript objects do. You can even store functions, as they are first class citizens.

http://en.wikipedia.org/wiki/JSON#Object_references

var anna = {name: "Anna"};
var bob = {name: "Bob", knows: [anna]};
var charlie = {name: "Charlie", knows: [anna, bob]}
anna.knows = [charlie, bob];

// 'Bob'
alert(charlie.knows[0].knows[1].name)

// -------------------------------------------------

var call = function(destination) {
    alert(this.name + " calls " + destination.name);
}
bob.call = call;

// 'Bob calls Charlie'
bob.call(charlie);

But beware of infinite loops!
(bob knows anna, anna knows bob, bob knows anna, ...)

In JSON, relationships can only be represented by value (which is ideally the unique ID of a record). You basically duplicate the name, and need to look up the entry with this name to find what it refers to.

var ob_from_json = JSON.parse('
    {
        "bob": {"name": "Bob", "knows": ["anna"]},
        "anna: {"name": "Anna", "knows": ["bob"]}
    }
');

// 'Anna'
ob_from_json[ob_from_json["bob"].knows[0]].name