How to delete N numbers of documents in mongodb

mongodb

In my collections, documents contains key like status and timestamp. When I want to find latest ten documents then I write following query

db.collectionsname.find().sort({"timestamp"-1}).limit(10)

This query gives me results which I want but when I want to delete latest ten documents then I was writing the following query

db.collectionsname.remove({"status":0},10).sort({"timestamp":-1})

but it shows following error TypeError: Cannot call method 'sort' of undefined and again I wrote the same query as below db.collectionsname.remove({"status":0},10) It deletes only one document. So how can I write a query which deletes ten latest documents and sorts on timestamp?

You can't set a limit when using remove or findAndModify. So, if you want to precisely limit the number of documents removed, you'll need to do it in two steps.

db.collectionName.find({}, {_id : 1})
    .limit(100)
    .sort({timestamp:-1})
    .toArray()
    .map(function(doc) { return doc._id; });  // Pull out just the _ids

Then pass the returned _ids to the remove method:

db.collectionName.remove({_id: {$in: removeIdsArray}})

FYI: you cannot remove documents from a capped collection.

Let N be number of records to delete.

    db.collectionName.find().limit(N).forEach(doc => 
     { 
       db.collectionName.remove({_id:doc._id})
     }
    )

You can pipeline the output of find query mapping to use _id and performing a remove based on $in query such as:

db.collection.remove({_id: 
    { $in: db.collection.find().sort({timestamp:-1}).limit(100).map(a => a._id) }
})

To remove N number of documents in your collection myCollection:

db.getCollection('myCollection').find({}).limit(N).forEach(function(doc){
    db.getCollection('myCollection').remove({_id: doc._id});
})

How to delete N numbers of documents in mongodb

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