output

0 undefined
1 undefined
>

update.js

var count = 0; 
var c = db.Supplier.find(); 
while(c.hasNext()) {
    var i = c.next(); 
    var col = i.supplies; 
    for (j in col) { 
        col[j].price = {
            wholesalePrice: col[j].price, 
            retailPrice: col[j].suggestedPrice
            
        }; 
        delete col[j].suggestedPrice; 
    } 
    print(count++,  db.Supplier.update({id: i._id}, {$set: {supplies: col}}));
}