First, check the available collections into your database mydb.

  1. >use mydb switched to db mydb >show collections mycol mycollection system. indexes tutorialspoint > Now drop the collection with the name mycollection.
  2. >db. mycollection. drop() true > …
  3. >show collections mycol system. indexes tutorialspoint >

db.collection.drop In MongoDB, db.collection.drop() method is used to drop a collection from a database. It completely removes a collection from the database and does not leave any indexes associated with the dropped collections.

drop() method and drop command create an invalidate Event for any Change Streams opened on dropped collection. Starting in MongoDB 4.4, the db. collection. drop() method and drop command abort any in-progress index builds on the target collection before dropping the collection.

You can delete a table, or collection as it is called in MongoDB, by using the drop() method. The drop() method takes a callback function containing the error object and the result parameter which returns true if the collection was dropped successfully, otherwise it returns false.

It cleans the database by dropping the user collections and emptying the system collections. This script cleans everything within only one particular Mongo database. It erases all collections in this database.

MongoDB supports horizontal scaling through Sharding , distributing data across several machines and facilitating high throughput operations with large sets of data.

To delete a MongoDB Collection, use db.collection.drop() command.

The MongoDB shell provides the following methods to delete documents from a collection:

  1. To delete multiple documents, use db. collection. deleteMany() .
  2. To delete a single document, use db. collection. deleteOne() .

Drop a Collection

  1. Click the trash can icon to delete a collection. From the Collections screen, click on the trash can for the collection to delete. …
  2. Confirm the collection to delete. In the dialog, enter the name of the collection to delete.
  3. Click Drop Collection to drop the collection.

The drop command removes the specified collection or view from the Atlas Data Lake storage configuration. Use the wildcard * to remove all collections generated by the wildcard collection function (that is, collectionName() ), including the wildcard collection rule itself.

MongoDB uses reader-writer locks that allow concurrent readers shared access to a resource, such as a database or collection, but in MMAPv1, give exclusive access to a single write operation. WiredTiger uses optimistic concurrency control. WiredTiger uses only intent locks at the global, database and collection levels.

/data/db directory Create the data directory Before you start MongoDB for the first time, create the directory to which the mongod process will write data. By default, the mongod process uses the /data/db directory.

To remove or delete field in MongoDB

  1. For single Record db. getCollection(‘userData’). update({}, {$unset: {pi: 1}})
  2. For Multi Record db. getCollection(‘userData’). update({}, {$unset: {pi: 1}}, {multi: true})

mongod is the primary daemon process for the MongoDB system. It handles data requests, manages data access, and performs background management operations. This document provides a complete overview of all command line options for mongod .

If you are using MongoDB 2.0 or higher, the mongo shell supports both:

  1. cls command.
  2. Ctrl+l (clear screen)

MongoDB is faster than MySQL due to its ability to handle large amounts of unstructured data when it comes to speed. It uses slave replication, master replication to process vast amounts of unstructured data and offers the freedom to use multiple data types that are better than the rigidity of MySQL.

Both these databases support multi-document transactions, but with key differences: MongoDB supports read and writes to the same documents and fields in a single database transaction. DynamoDB lacks support for multiple operations within a single transaction.

As a NoSQL database, MongoDB is scalable as its data is not coupled relationally. Data is stored as JSON-like documents which are self-contained. This allows those documents to be easily distributed across multiple nodes through horizontal scaling.

They do the same. The difference is the values that return.

Uninstall MongoDB in Ubuntu via command line in 3 easy steps

  1. Step 1: Stop the service. sudo service mongod stop.
  2. Step 2: Remove packages. sudo apt-get purge mongodb-org*
  3. Step 3: Remove data directories. sudo rm -r /var/log/mongodb sudo rm -r /var/lib/mongodb. -r means recursive.

To delete all documents from a collection, pass an empty filter document {} to the db.collection.deleteMany() method. The method returns a document with the status of the operation.

The MongoDB Shell, mongosh , is a fully functional JavaScript and Node. … x REPL environment for interacting with MongoDB deployments. You can use the MongoDB Shell to test queries and operations directly with your database. mongosh is available as a standalone package in the MongoDB download center.

MongoDB Compass is a powerful GUI for querying, aggregating, and analyzing your MongoDB data in a visual environment. Compass is free to use and source available, and can be run on macOS, Windows, and Linux.