Query for documents where array size is greater than 1

I have a MongoDB collection with documents in the following format:

{
  "_id" : ObjectId("4e8ae86d08101908e1000001"),
  "name" : ["Name"],
  "zipcode" : ["2223"]
}
{
  "_id" : ObjectId("4e8ae86d08101908e1000002"),
  "name" : ["Another ", "Name"],
  "zipcode" : ["2224"]
}

I can currently get documents that match a specific array size:

db.accommodations.find({ name : { $size : 2 }})

This correctly returns the documents with 2 elements in the name array. However, I can't do a $gt command to return all documents where the name field has an array size of greater than 2:

db.accommodations.find({ name : { $size: { $gt : 1 } }})

How can I select all documents with a name array of a size greater than one (preferably without having to modify the current data structure)?

---

Update:

For mongodb versions 2.2+ more efficient way to do this described by @JohnnyHK in another answer.

---

1.Using $where

db.accommodations.find( { $where: "this.name.length > 1" } );

But...

Javascript executes more slowly than the native operators listed on this page, but is very flexible. See the server-side processing page for more information.

2.Create extra field NamesArrayLength , update it with names array length and then use in queries:

db.accommodations.find({"NamesArrayLength": {$gt: 1} });

It will be better solution, and will work much faster (you can create index on it).

---

在MongoDB 2.2+中，有一种更高效的方法可以在查询对象键中使用数字数组索引。

// Find all docs that have at least a second name array element.
db.accommodations.find({'name.1': {$exists: true}})

---

I believe this is the fastest query that answers your question, because it doesn't use an interpreted $where clause:

{$nor: [
    {name: {$exists: false}},
    {name: {$size: 0}},
    {name: {$size: 1}}
]}

It means "all documents except those without a name (either non existant or empty array) or with just one name."

Test:

> db.test.save({})
> db.test.save({name: []})
> db.test.save({name: ['George']})
> db.test.save({name: ['George', 'Raymond']})
> db.test.save({name: ['George', 'Raymond', 'Richard']})
> db.test.save({name: ['George', 'Raymond', 'Richard', 'Martin']})
> db.test.find({$nor: [{name: {$exists: false}}, {name: {$size: 0}}, {name: {$size: 1}}]})
{ "_id" : ObjectId("511907e3fb13145a3d2e225b"), "name" : [ "George", "Raymond" ] }
{ "_id" : ObjectId("511907e3fb13145a3d2e225c"), "name" : [ "George", "Raymond", "Richard" ] }
{ "_id" : ObjectId("511907e3fb13145a3d2e225d"), "name" : [ "George", "Raymond", "Richard", "Martin" ] }
>

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