mongodb move documents from one collection to another collection

Question

How can documents be moved from one collection to another collection in MongoDB?? For example: I have lot of documents in

Answer 1

May be from the performance point of view it's better to remove a lot of documents using one command(especially if you have indexes for query part) rather than deleting them one-by-one.

For example:

db.source.find({$gte: start, $lt: end}).forEach(function(doc){
   db.target.insert(doc);
});
db.source.remove({$gte: start, $lt: end});