How to Create MongoDB database with the CLI

MongoDB is an open-source, NoSQL JSON-like document database that is created using C++ language. Creating a MongoDB Database is pretty straight forward. This guide is all about how to create MongoDB Database with the CLI ie mongosh.

Prerequisite

• MongoDB installation

In this previous guide, we already installed MongoDB.

Connect to the MongoDB shell with the credentials that you’d already set using the following command:

# mongosh --port 27017 --authenticationDatabase "admin" -u "mongoadmin" -p
Enter password: **********
Current Mongosh Log ID:	64d51e3846bf0d89d2b526bc
Connecting to:		mongodb://<credentials>@127.0.0.1:27017/?directConnection=true&serverSelectionTimeoutMS=2000&authSource=admin&appName=mongosh+1.10.3
Using MongoDB:		6.0.8
Using Mongosh:		1.10.3

For mongosh info see: https://docs.mongodb.com/mongodb-shell/

Show MongoDB Databases

Using the command below, we are able to list the already existing databases.

test> show dbs
admin   132.00 KiB
config   72.00 KiB
local    72.00 KiB

Please note that admin and local are default databases for every MongoDB instance.

Create MongoDB database

There is no ‘create’ command in the mongosh. For you to create a database, you will first need to switch the context to a non-existing database using the use command:

use DATABASE_NAME

Example:

test> use technnix_db
switched to db technnix_db

technnix_db> show dbs
admin   132.00 KiB
config   96.00 KiB
local    72.00 KiB
technnix_db> 

The use keyword is used to switch to the mentioned database in case it exists or it creates a new one if its non-existent.

MongoDB only creates the database when you first store data in that database. This data could be a collection or a document. This is the reason why we are unable to see the newly created database from the command above.

Collection:  equivalent of an RDBMS Relational Database Management System table. Its a collection/groupings of MongoDB Documents.

Document: The basic unit of data in MongoDB.

Insert Data to Database

db.collection.insert() command is used to add a document to the database

technnix_db> db.user.insert({name: "Ezekiel Mogaka", age: 35, website: "technnix.com"})
DeprecationWarning: Collection.insert() is deprecated. Use insertOne, insertMany, or bulkWrite.
{
  acknowledged: true,
  insertedIds: { '0': ObjectId("64d529c046bf0d89d2b526bd") }
}

Verification

Lets verify whether the database was created and data inserted onto it.

technnix_db> show dbs
admin        132.00 KiB
config       108.00 KiB
local         72.00 KiB
technnix_db   40.00 KiB
technnix_db> db.user.find()
[
  {
    _id: ObjectId("64d529c046bf0d89d2b526bd"),
    name: 'Ezekiel Mogaka',
    age: 35,
    website: 'technnix.com'
  }
]

Conclusion

That it for now. For more information, please refer to the official MongoDB documentation.