sorting documents using multiple keys

[Borja Martín]

Hi,
I'm pretty new to couchdb and I'm not quite sure if this can be done. Is
there any way to sort the retrieved documents by a certain field when I
select them using multiple keys?
I have these documents for example:
{
  _id : "a",
  tags : ["foo"],
  created_at : "20091201"
},

{
  _id : "b",
  tags  : ["bar"],
  created_at : "20091231"
},

{
  _id : "c",
  tags  : ["foo", "bar"],
  created_at : "20091215"
},


Then, I create a view to store the documents for each tag:

function(doc) {
    for(var idx in doc.tags) {
      emit(doc.tags[idx], doc);
    }
  }

and eventually I can make a POST request using the keys parameter in order
the retrieve all the documents that have one or more of the given tags.
The problem is that I don't know how to sort the result by the field
created_at and I can't use it in the emit function within the key as I will
not know the value for it (and the documents can different values for it)

Any idea how to achieve this?

Thanks in advance

Regards
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