[Mongo] Copy Apr data to May

1. Check Apr

db.Answer.find({createdAt: {$gte: ISODate("2015-03-31T12:00:00Z"), $lte: ISODate("2015-04-30T12:00:00Z")}, organisationId: 1514});

2. Copy Apr to New Table

db.Answer.find({createdAt: {$gte: ISODate("2015-03-31T12:00:00Z"), $lte: ISODate("2015-04-30T12:00:00Z")}, organisationId: 1514}).forEach( function(x) {
db.AnswerCopy.insert(x)
});
db.AnswerCopy.count();

3. Update Date to May

db.AnswerCopy.find().forEach(function(a){
  db.AnswerCopy.update(a, {$set:{"createdAt" : ISODate("2015-05-10T00:00:00Z")}});
});
db.AnswerCopy.count();

4. Recreate object id for unique as will populate to Answer

db.AnswerCopy.find().snapshot().forEach(function(doc){
var id=doc._id; doc._id=ObjectId(); db.AnswerCopy.insert(doc); db.AnswerCopy.remove({_id:id});
});
db.AnswerCopy.count();

5. Populate to Answer

db.AnswerCopy.find().forEach( function(x) {
db.Answer.insert(x)
});

6. Check

db.Answer.find({createdAt: {$gte: ISODate("2015-05-01T00:00:00Z")}});