Skip to main content

What is MonGoDB??

Share on Google Plus
Now a Days, we are hearing a lot about MongoDB.

So, in this post I will try to briefly introduce to MongoDB.

MonGoDB is "Non-Relational, JSON, Document Store".

Explaining in detail,

Non-Relational, --> The DB we use most like SQl, Oracle are Relational DBs(RDBMS). They do have the fixed schemas, lots of tables. So Non-relational in nothing like that.

JSON : (JavaScript Object Notation) : It is basically a document with information in the form of key value pair.

for example,


thats it. 
A simple JSON document where name and address are key
and "lorem" and "ipsum" are corresponding values.

So, MongoDB is the Non Relational database which stores information using DOCUMENT and that document is a JSON document.

MongoDB stores collections of documents.
(Consider the above exxample as collection  "Person"  with a document)(will elaborate it later more)

Need of MongoDB:
The Databases we use now a days, mostly SQL, Oracle(RDBMS) provides lots of functionaily but they lack one thing, which is Performance and Scalibility.So, MongoDB aims at providing the same level of functionality but providing high performance and scalibility.

One more advantage of MongoDB is that it supports Dynamic Schema.
Meaning is RDBMS(SQL,Oracle etc), tables have fixed Schema like a table can have fixed colums and these columns cant be changed at run-time.

But in MongoDB, columns can be changed.

Suppose a collection "Person", can have two documents,
1st Document

2nd Doc.


 So, these two docs have "name" has in common but 1st document has "address" while 2nd doesnt have this. Same with "DOB".
This is perfectly valid in MongoDB but not possible in SQL,

Also, there is one more thing,

Consiser a document,

DOB: "13-Aug",
fav_color : ['red','blue']

Yeah, dont get confused,.
This document contains a list name, fav_color and DOB.
only difference is fav_color is storing an array of value instead of a single value.

 This is possible in SQl, but you cant store all this information in one table. There needs a different table for fav_Color..

 But there are also some limitations of MongoDB,
a) It doesn't support Joins
b) doesnt support Transactions

To install it,
Use the link :
Download the version.

Then extract the content to a directory (say C:\MongoDB)
Now before frirng any command it needs "/data/db" directory in current directory. 
So create the dircrctory as 

md C:\data
md C:\data\db

now navigate to C:\MongoDB and run mongod.exe in a command prompt.

now to create a db, open another command prompt and type "mongo.exe" and press Enter,

This should take you to MongoDB console,

Now create DB using

use test       // test is DB name

to add data to collection{name:"lorem",address:"ipsum"}) 
db -> keywod
persons-> collection name
save -> function

to view the save doc


Thats it..

Hope this will help...

You can also check our Microservices post
Introduction to Microservices


Popular posts from this blog

Login with Google Account using PHP / Javascript using OAuth2.0

Login with Google Account using PHP with code
This post have Complete Code for Login / Sign-in  with google Account  using PHP / Javascript with oAuth2.0

Basically today we have seen almost every website needs you to register yourself before you can post or take part in any discussions to the website. But it become a tedious task to register and login to many different sites. Solution is to provide the users the option to Login with existing Google / Facebook account as almost everyone have Facebook and Google account..

In this post, I am going to explain how to integrate the Google Login / Sign in  for your website.

For this,  First you need to create your Client ID, Client Secret and your developer API key.

For this go to

Click on the button Create Project. A new window will open up. Please select Create Project / or select already created Project.

It will then ask for about type of Project. Please select Web-browser. Then it …

TCP Chat Server in Node.js

d.Hello all.

Today in this post, I am going to explain about how to use a "net" module in node.js and build a basic chat server.(i.e a TCP chat server)

For this, you need to use either telnet / netcat(nc).(I have tried it on netcat, simply google "netcat download")
(Dont worry about the script for now, i will upload it, just go through the tutorial to understand the concept)

So, lets begin,

first of all to use node "net" module , we need to import it in out script.

var net = require("net")

This will import the net module. Now moving ahead, we need to create a server. This is done by createServer  function(on simply Server function).

var server = net.createServer()

createServer has a callback whenever a client connects to a server.

var server = net.createServer(function(socket){


The code inside the createServer() function is callback(Hope you have know about the callbacks / event driven programming). This gets called whenever, a client gets c…