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Steps To Reproduce:
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db.collection.insertOne({

items: [

{

_id: ObjectId,

name: 'foobar'

{{ }}}

]

});

db.collection.aggregate([
{
$unwind: }}{{'$items.name'
{{ }}}
]);{{}}

Outputs nothing
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db.collection.insertOne({ items: [ { _id: ObjectId, name: 'foobar' {{ }}} ] }); db.collection.aggregate([ { $unwind: }}{{'$items.name' {{ }}} ]); {{}} Outputs nothing
CAR Domain/s:
None

Given the following document:

db.collection.insertOne({

items: [

{

_id: ObjectId,

name: 'foobar'

{{ }}}

]

});

Trying to `$unwind` the field path `$items.name` outputs nothing.

On the other hand, the output of this:

db.collection.aggregate([
{
$project: {
{{ type: { $type: '$items.name' }}}
{{ }}}
{{ }}}
]);

is the following:

{{{}}
"_id" : ObjectId("..."),
"type" : "array"
}

If the expression `$items.name` resolves to an array then why can I not `$unwind` this field path?

is depended on by

MONGOID-5556 #tally should support splatting array results

is duplicated by

SERVER-73888 Aggregation Pipeline: $unwind always gives an empty result with nested fields

is related to

SERVER-97149 $unwind with a path that traverses through arrays omits results

Assignee:: Katya Kamenieva
Reporter:: Amit Beckenstein
Participants:: Amit Beckenstein, Asya Kamsky, Chris Harris, Johnny Shields, Katya Kamenieva, Kelsey Schubert, William Tan
Votes:: 1 Vote for this issue
Watchers:: 9 Start watching this issue