MongoDB Basics and mongo Shell Commands

• NO SQL database.
• Data is stored as BSON format (i.e. same as our good old JSON but more optimized, see picture!)
  
• Comparison with RDBMS:
• Database = "Database"
• Tables = "Collections"
• Rows = "Document"

 

mongo vs mongod

-> mongo

A Programmer writes Commands in this Shell.
Automatically starts at 27017 port of our local host
The Command line Shell that connects to specific instance of "mongod" (mongoDataBase).

-> mongod

The Host Process of our Database.

    FUN FACT :- mongo was also called mongosh before.

Handy mongo shell commands.

db =>	shows the current working db
use name_of_the_database   =>	creates(if it doesn't exist)  or switches(if it already exists) to the named database
show dbs =>	shows all databases
db.dropDatabase()	deletes the current working db
show collections =>	shows all collections

    FACT - A database doesn't count to be made if it doesn't have any collection(document). 

db.collection_name.insert({"name":"rishabh", "branch":'IT"}); 

db.collection_name.insertOne({"name":"rishabh", "branch":'IT"}); 

db.collection_name.insertMany([{"name":"rishabh", "branch":'IT"},{"name":"gourav" , "branch":"IT"}]);

 

CLOSING NOTE - That's pretty much all the commands we will ever use as a software developer directly on mongo Shell.

Next up : Please see Authentication in MongoDB Blog for database Permissions and Users.