Update a subdocument with one single query or multiple (mongoose)? - mongodb

Question

This is a part of my document:
var actions = {
title: 'Change of windows'
energySavings:[
{
_id: 234324234,
mainCategory: 'Elektricitet',
subCategory: 'Belysning',
value: 1
},
{
_id: 5434534543,
mainCategory: 'Elektricitet',
subCategory: 'Utrustning',
value: 1
}
]
}
I want to be able to update energySavings, add items and remove items. This could be done in three separate queries. Or, I could all do it in just one
var givenAction = JSON.parse(req.body.action);
mongoose.model('Action').findOne({actionId: req.params.actionId}, function(err, action){
action.energySavings = givenAction.energySavings;
action.save(function(err, savedAction){
res.status(200).send(savedAction);
});
})
Way less code then three separate queries. However, if the client side programmer makes a mistake, for example empty the entire array and save it, we will have a problem. Is there a best practice to this, make in one query or several with more control?

Answer 1

You can also update the document with findOneAndUpdate of mongoose. For case the empty array added mistakenly, you need to check if the query is empty or not before updating or adding that.
var givenAction = JSON.parse(req.body.action);
mongoose.model('Action').findOneAndUpdate({
actionId: req.params.actionId
}, {
$set: {
energySavings: givenAction.energySavings
}
}, callback);
You can use $push to add as new items, and $pull to remove items instead of $set to updating it. I don't think it is not a good choice to update energySavings, add items and remove items in one query.