Joining documents in Couchbase and using aggregate functions

Couchbase Server
1

I have these 4 documents

Document 1

{
  "First_Name": "dhw",
  "Type": "GLAccount",
  "Acc_no": 1,
  "Last_Name": "irtahow"
}

Document 2

{
  "Marks": 13,
  "Type": "GLEntry",
  "Acc_no": 1
}

Document 3

 {
  "Marks": 85,
  "Type": "GLEntry",
  "Acc_no": 1
}

Document 4

{
  "Marks": 93,
  "Type": "GLEntry",
  "Acc_no": 1
}

Now I want to use a sum function Documents 2,3 and 4 and then join it with Document 1. So the result of my query should be like

Acc_no   First_Name   Last_Name      Sum(marks)
1           "dhw"     "irtahow"         191

So here you see I want to first sum all the marks of a particular Acc_No and then output its sum of marks and first name and last name.
I am able to sum the marks but not able to simulate the join.

2

Have you taken a look at N1QL.