Question

I am having a problem where I need to update a specific field found in arrays contained in a bigger array that match certain criteria as of MongoDB v2.2.3.

I have the following mongodb sample document.

{
  _id: ObjectId("50be30b64983e5100a000009"),
  user_id: 0
  occupied: {
    Greece: [
      {
        user_id: 3,
        deadline: ISODate("2013-02-08T19:19:28Z"),
        fulfilled: false
      },
      {
        user_id: 4,
        deadline: ISODate("2013-02-16T19:19:28Z"),
        fulfilled: false
      }
    ],
    Italy: [
      {
        user_id: 2,
        deadline: ISODate("2013-02-15T19:19:28Z"),
        fulfilled: false
      }
    ]
  }
}

Each country in the occupied array has its own set of arrays.

What I am trying to do is find the document where user_id is 0, search through the occupied.Greece array only for elements that have "deadline": {$gt: ISODate(current-date)} and change their individual “fulfilled” fields to true.

I have tried the $ and $elemMatch operators but they match only one, the first, array element in a query whereas I need it to match all eligible elements by the given criteria and make the update without running the same query multiple times or having to process the arrays client-side.

Is there no server-side solution for generic updates in a single document? I am developing using PHP though a solution to this should be universal.

Answer 1

I’m afraid this is not possible. From the documentation:

Remember that the positional $ operator acts as a placeholder for the first match of the update query selector. [emphasis not mine]

This is tracked in the MongoDB Jira under SERVER-1243.

There’s quite a number of related feature requests in the jira, mostly under the topic ‘virtual collections‘.