Mongodb update several documents with different values

Question

i am trying to update several documents in mongodb with different values each.

In mysql I do something like this:

$objs = array(array('id'=>1,'lat'=>37.123,'lng'=>53.123),...,array('id'=>n,'lat'=>x,'lng'=>y));

$sql = "INSERT INTO objects (objectId,latitude,longitude) VALUES";
        foreach ($objs as $obj) {
            $id = $obj['id'];
            $lat = $obj['lat'];
            $lng = $obj['lng'];
            $sql .= "($id,$lat,$lng),";
        }
        $sql = substr_replace($sql ," ",-1);    
        $sql.= "ON DUPLICATE KEY UPDATE latitude=VALUES(latitude),longitude=VALUES(longitude)";

Now, is it possible to do it in mongodb?

Answer 1

This question has already been asked here: MongoDB: insert on duplicate key update

In mongodb you can use the upsert option on Update command. It's similar as ON DUPLICATE KEY UPDATE. Definition of upsert option:

A kind of update that either updates the first document matched in the provided query selector or, if no document matches, inserts a new document having the fields implied by the query selector and the update operation.

I have consulting the PHP Mongo Documentation. In example #2 of MongoCollection:Update command you have your response.

Example:

<?php
$objs = array(array('id'=>1,'lat'=>37.123,'lng'=>53.123), array('id'=>n,'lat'=>x,'lng'=>y));

foreach($objs as $obj)
{
    // Parameters: [1] Description of the objects to update. [2] The object with which to update the matching records. [3] Options 
    $collection->update(array("id" => $obj["id"]), $obj, array("upsert" => true));
}

?>

Answer 2

If you're duplicate key in your SQL is referencing the ID field, then it would be as follows:

// Your big array thing from your example
$objs = array(array('id'=>1,'lat'=>37.123,'lng'=>53.123),...,array('id'=>n,'lat'=>x,'lng'=>y));
// Start a new MongoClient
$m = new MongoClient();
// Select the DB and Collection
$collection = $m->selectCollection('DBNAME', 'COLLECTIONNAME');
// Loop through $objs
foreach($objs as $obj) {
    $collection->update(
        // If we find a matching ID, update, else insert
        array('id' => $obj['id']), 
        // The data we're inserting
        $obj, 
        // specify the upsert flag, to create a new one if it can't find
        array('upsert' => true) 
    );
}

Basically, the update command (with upsert set to true) will either update an existing document that matches the first parameter of the update, or insert a new document. Mentor Reka's post talks more about how upserts work, but the code above should do exactly what you're looking for.