Mongoose and findAndModify
You don't need to use findAndModify for this as you don't need the original document. So you can just use update like this:
MyModel.update({ _id: '52261c53daa9d6b74e00000c', someAdditionalFlag: 156}, { $set: {someAdditionalFlag: newValue }},function(err, numAffected) { ... });In the callback, numAffected will be 1 if a change was made, otherwise 0.