ElasticSearch Nested Objects

I have a question on nested and parent/child objects.

Below are my sample nested documents –

DocumentID: 1

{
    "UserID": 1,
    "FirstName": "User1 First",
    "LastNameName": "User1 Last",
    "Assignments": [
        {
            "Role": "Role1",
            "Permission": "P1",
            "Value": "V1"
        },
        {
            "Role": "Role2",
            "Permission": "P2",
            "Value": "V2"
        }
    ]
}

DocumentID: 2

{
    "UserID": 2,
    "FirstName": "User2 First",
    "LastNameName": "User2 Last",
    "Assignments": [
        {
            "Role": "Role1",
            "Permission": "P1",
            "Value": "V1"
        }
    ]
}

Below are my questions –

  1.   Is it mandatory to put “type:nested” for nested field “Assignments”? "Assignments' is an array which will have multiple sub-documents.
    
  2.   We mostly use queryString method for querying on these documents. Our queries generally are like below – 
    

((Assignments.Role=Role1 AND Assignments.Role=Role2) OR (Assignments.Role=Role3 AND Assignments.Role=Role5) OR (Assignments.Role=Role3))
There can be multiple AND\OR conditions. We get expected results with above query. So do we have to add type:nested for nested field?
3. Also, if we use parent-child documents then can we add same child (same 'assignments' object in above case) to multiple parents?
I have gone through below link and it seems that there are few dis-advantages of adding type=nested property for nested field.

Request you to please provide your valuable suggestion.

Thanks,
Sameer

you might like to look @ this thread Parent/Child functionality where the discussion related to nested v/s parent/child happened. though doesn't answer all ur Qs :slight_smile: