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Basic commands on MongoDB.

This blog will include the basic commands on MongoDB including the  'CRUD' operations.

To gain access to MongoDB open up the command prompt and run the command  'mongod'  to start the server, and open up a separate command prompt and run the command  'mongo'  to access the MongoDB.

Show all the available databases.





Create new database.

In this example a new database called  'mycustomers'  has been created.




Once a database is created and if it does not have data, that database will not be visible when   'show dbs'  command is used.





Show the current working databases.

To display the current working database  'db'  command is used. Since the working database is   'mycustomers' ,  'db' command results mycustomers.



Adding a collection to the database.



Displaying the collection of the database.




Deleting the collection of the database.

In this example there are two collections inside  'mycustomers'  database.



And in this example 'mycustomer'  collection is dropped using   'drop()'




Inserting a field to the collection.



Displaying the field of the collection.



Updating the field of the collection.




Once the field is updated it can be viewed by  'find()' 




Deleting the field of the collection.


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