mongodb, get the result line after update

Question

mongodb, get the result line after update

I'm working with mongodb, node.js and socket.io and I'm trying to reduce the number off access to the database. I need to update a line ; and after to return the updated line this is how I do :

db.collection('users').update({_id:targetID}, {$set: { 'property': 'value' }}, {safe:true}, function(err, result) {
    db.collection('users').find({_id:targetID}).toArray(function(error, results){
        //a socket.io resend the content
    });
});

It works, but I really fell like I'm having a useless step here. The callback of the update function seems to be a boolean.

BTW, is there a better documentation than this one : http://docs.mongodb.org/manual/applications/update/ ? I'd like to find a list of properties and methods. The {safe:true} for instance. It seems not working without it but I can't find it in the reference.

Maybe I'm completely wrong and this is not the way I should do it. If you have a better idea... :)

node.js
mongodb
socket.io

Answer 1

You can use findAndModify to do this efficiently:

db.collection('users').findAndModify(
    {_id: targetID}, [], 
    {$set: { 'property': 'value' }}, 
    {new: true}, // Return the updated doc rather than the original
    function(err, result) {
        // result contains the updated document
    }
);