How to get the latest and oldest record in mongoose.js (or just the timespan between them)

Question

Basic problem

I have a bunch of records and I need to get latest (most recent) and the oldest (least recent).

When googling I found this topic where I saw

Answer 1

for version ~3.8 mongoose

to find the last entry

model.findOne().sort({ field: 'asc', _id: -1 }).limit(1)

or using

model.findOne().sort({ field: -_id }).limit(1)

Answer 2

collectionName.findOne().sort({$natural: -1}).limit(1).exec(function(err, res){
    if(err){
        console.log(err);
    }
    else{
        console.log(res);
    }
}

This will give you the last document recorded on the database. Just follow the same concept.

Answer 3

Mongoose 3.x is complaining about the [] parameter in your findOne calls as the array format is no longer supported for the parameter that selects the fields to include.

Try this instead to find the newest:

Tweet.findOne({}, {}, { sort: { 'created_at' : -1 } }, function(err, post) {
  console.log( post );
});

Change the -1 to a 1 to find the oldest.

But because you're not using any field selection, it's somewhat cleaner to chain a couple calls together:

Tweet.findOne().sort({created_at: -1}).exec(function(err, post) { ... });

Or even pass a string to sort:

Tweet.findOne().sort('-created_at').exec(function(err, post) { ... });

Answer 4

Fast and Simple - One Line Solution

Get 10 latest documents

MySchema.find().sort({ _id: -1 }).limit(10)

Get 10 oldest documents

MySchema.find().sort({ _id: 1 }).limit(10)

In case you want sorting based on some other property i.e. createdAt and get the oldest or latest. Again it is similar to the above query.

MySchema.find().sort({ createdAt: 1 }).limit(10)  // oldest docs
MySchema.find().sort({ createdAt: -1 }).limit(10) // latest docs

Answer 5

We have method called sort using that we can able to get first element(old document) which means 1 for sort field or last element(new document) which means -1 for sort field of collection.