What is the difference between GUID and UniqueId? They are both globally unique ids and from the client side we can see they are not the same:
ctx = new SP.ClientContext();
web = ctx.get_web();
list = web.get_lists().getByTitle("Issues");
item = list.getItemById(1);
ctx.load(item);
ctx.executeQueryAsync(function() {
console.log("GUID: " + item.get_item("GUID").toString());
console.log("UniqueId: " + item.get_item("UniqueId").toString());
console.log("ID: " + item.get_item("ID").toString());
});
Results in:
GUID: d2bcec49-5e88-494a-a141-4f4275363d79
UniqueId: 98237e32-67aa-4f95-887c-7567d0ab714e
ID: 1
Server side has SPList.GetItemByUniqueId so does that mean generally UniqueId should be used?