I have the following schema in my taxon collection :
{
"_id": 1,
"na": [ "root_1",
"root_2",
"root_3" ],
"pa": 1
},{
"_id": 2,
"na": [ "name_1",
"name_2",
"name_3"],
"pa": 1
},{
"_id": 4,
"na": [ "otherName_1",
"otherName_2",
"otherName_3"],
"pa": 2
}
Every document is related to another by the parent field, which corresponds to the _id of it's parent.
To the following result, recursive search is performed.
{ "_id": 4,
"nameList": [ "otherName_1",
"name_1",
"root_1"]
}
From document with a certain _id, get the first item of an array of each parent until document with _id: 1 is reached
I currently get this result by performing X queries (one by parent document, here 3 for example), but I'm pretty sure that this can be achieved using a single query. I already looked at the new $graphLookup operator, but couldn't manage to get my way with it...
Is it possible to achieve this in a single query using MongoDB 3.4.1?
Edit
I would run this for 50 documents each time, so the optimal solution would be to combine everything in a single query
for example, it would looks like
var listId = [ 4, 128, 553, 2728, ...];
var cursor = db.taxon.aggregate([
{$match:
{ _id: {$in: listId}}
}, ...
)];
and would output :
[{ "_id": 4,
"nameList": [ "otherName_1",
"name_1",
"root_1"]
}, { "_id": 128,
"nameList": [ "some_other_ame_1",
"some_name_1",
"root_1"]
}, { "_id": 553,
"nameList": [ "last_other_ame_1",
"last_name_1",
"root_1"]
} ... ]
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