README.md

Be able to query mongodb records in the given timeperiod by ObjectId

var timestampToObjectId = require('timestamp-objectId');
// timestampToObjectId = function(timestamp)
// timestamp could be both String and actual Timestamp

db.mycollection.find({
  _id: {
    $gt: timestampToObjectId('1980/05/25'),
    $lt: timestampToObjectId(1367413318476)
  }
});

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