[SERVER-8088] $unwind of non-array should be allowed - MongoDB Jira

XML

Word

Printable

JSON

This would effectively just output the existing field.

> db.reg.find()

{ "_id" : 1, "text" : "foo" }

{ "_id" : 2, "text" : "bar" }

{ "_id" : 3, "text" : "Bar" }

{ "_id" : 4, "text" : [ "bar", "foo" ] }

>db.reg.aggregate({$match:{text:/ba/i}}, {$unwind:"$text"})

...

	"errmsg" : "exception: $unwind:  value at end of field path must be an array",

	"code" : 15978,

	"ok" : 0

This will be important for collections where some document fields may be arrays, but some may not.

is documented by

DOCS-9024 $unwind of non-array should be allowed

is duplicated by

SERVER-11718 Allow aggregation framework to optionally pass through non-arrays through $unwind

is related to

SERVER-12685 Expand $unwind behavior to include empty documents optionally

Participants:: Asya Kamsky, Daniel Pasette, Eduardo Manso, Eliot Horowitz, Githook User, Jon Rangel, Laurent Dollé, Mathias Stearn, Scott Frenkiel, Scott Hernandez