Question

My dataset is complete in the DB; however I want to create a new field on each of the documents in the db. This new field I want to be derived by some of my input along with other fields that are currently in the database:

IE:

Document: 
{ 
   "_id":myId,
   "city":"fooville",
   "state":"bar"
}

Then I want to take and iterate through every entry and add something like this:

Document:
{
   "_id":myId,
   "city":"fooville",
   "state":"bar",
   "cityState":"fooville, bar"
}

Is there an easy way to do this? Trying to avoid re-inserting the entire dataset.

Thank you in advance for your help

(Mongo is awesome)

Answer 1

Something like this:

$results = $collection->find();

// iterate through the results
foreach ($results as $results) 
{

    $collection->update(array("_id" => new MongoId($result['_id'])), 
                        array('$set' => array("cityState" => sprintf("%s, %s", $result['city'], $result['state']))));

}

I haven’t tested it….but it should work…