How to update date field in mongo console?

Question

For example I want to update all records to \'2012-01-01\' ( \"time\" : ISODate(\"2011-12-31T13:52:40Z\") ).

db.test.update( { time : \'2012-01-01\' }, false,          


        

Answer 1

You need to create a new ISODate object like this:

db.test.insert({"Time" : new ISODate("2012-01-10") });

This is true both for updates and for queries. Note that your query syntax is incorrect, it should be

db.test.update({ criteria }, { newObj }, upsert, multi);

For example, to update all objects, consider

db.test.update( {}, { $set : { "time" : new ISODate("2012-01-11T03:34:54Z") } }, true, true);

Also note that this is very different from

db.test.update( {}, { "time" : new ISODate("2012-01-11T03:34:54Z") }, true, false);

because the latter will replace the object, rather than add a new field to the existing document or updating the existing field. In this example, I changed the last parameter to false, because multi updates only work with $ operators.

Answer 2

You can do this in the old-school way by creating ISO date

  db.test.update({_id : 1}, {
      $set : {
         "time" : new ISODate("your current date")
      }
  });

But note that with new Mongo 2.6 you will be able to update date to a current date really easy with $currentDate.

db.test.update( { _id: 1 }, {
  $currentDate: {
      time: true,
  },
})

Answer 3

If you need to convert an existing date field (imported from MySQL format 'yyyy-mm-dd' f.e.) to ISODate you can loop through the documents this way:

/usr/bin/mongo yourdbname --eval "db.yourcollectionname.find().forEach(function(doc){doc.yourdatefield = new ISODate(doc.yourdatefield);db.yourcollectionname.save(doc)});"