Filtering Mongo items by multiple fields and subfields - mongodb

Question

I have the following items in my collection:
> db.test.find().pretty()
{ "_id" : ObjectId("532c471a90bc7707609a3d4f"), "name" : "Alice" }
{
"_id" : ObjectId("532c472490bc7707609a3d50"),
"name" : "Bob",
"partner_type1" : {
"status" : "rejected"
}
}
{
"_id" : ObjectId("532c473e90bc7707609a3d51"),
"name" : "Carol",
"partner_type2" : {
"status" : "accepted"
}
}
{
"_id" : ObjectId("532c475790bc7707609a3d52"),
"name" : "Dave",
"partner_type1" : {
"status" : "pending"
}
}
There are two partner types: partner_type1 and partner_type2. A user cannot be accepted partner in the both of types. But he can be a rejected partner in partner_type1 but accepted in the another, for example.
How can I build Mongo query that fetches the users that can become partners?

Answer 1

When your user can only be accepted in one partner-type, you should turn it around: Have a field accepted_as:"partner_type1" or accepted_as:"partner_type2". For people who aren't accepted yet, either have no such field or set it to null.
In both cases, your query to get any non-accepted will then be:
{
data.accepted_as: null
}
(null matches both non-existing fields as well as fields explicitly set to null)

Answer 2

For me the logical schema would be this:
"partner : {
"type": 1,
"status" : "rejected"
}
At least that keeps the paths consistent between documents.
So if you want to stay away from using mapReduce type methods to find out "which field" it is on, and otherwise use plain queries and the aggregation pipeline, then don't vary field paths on documents. If you alter the "data" then that is the most consistent form.