MongoDB

The mongonetworkerror: connect econnrefused 127.0.0.1:27017 error occurs when a problem is connecting to a MongoDB server running on the localhost (127.0.0.1) on port 27017. The “ECONNREFUSED” means that the server actively refused the connection. Causes There might be a possibility that the MongoDB server is not running. You need to check the firewall because sometimes it … Read more

MongoDB stores data in BSON – Binary encoded JSON documents which supports a substantial, rich collection of types. Namely, Fields in BSON documents may hold arrays of values or embedded documents as a requirement. Therefore, the record in MongoDB is a document that is described below and a data structure formed of field and value … Read more

To some extent, the map and reduce phases were inspired by the map and reduce, the high-order functions widely used and well known in the functional programming world in JavaScript. As the name MapReduce implies, the map job is always performed before the reduce job. The Mapper will start by reading the data collection and building the Map with the required fields that we need to process and group … Read more

When it’s time to gather the metrics from MongoDB, there is no better solution than MongoDB aggregations. Aggregations are the functions that allow you to manipulate the data being returned from a MongoDB query. For example, aggregations operations can process the data records and return the computed results.  Mongodb Aggregate Aggregate function groups the records in … Read more