MognoDB Tutorial

MognoDB Tutorial - Chapter 1

MongoDB is an open-source document database, and leading NoSQL database. MongoDB is written in c++.

I am going to tell you that how can you learn MongoDB:

TAKE A LOOK ON THIS TABLE FOR A SIMPLE BRIEF RDBMS	MongoDB
Database	Database
Table	Collection
Tuple/Row	Document
Column	Field
Table Join	Embedded Documents
Primary Key	Primary Key (Default key _id provided by mongodb itself)
Database Server and Client
Mysqld/Oracle	mongod
mysql/sqlplus	mongo

First step:  You need to go in MongoDB folder where you had installed it
Like: C:\wamp\bin\mongodb\mongodb-win32-x86_64-2008plus-2.4.10\bin

Now you need to start mongodb server to double click on mongod.exe if it is already start if will blink the cmd and close.

Now you need to Double click on mongo.exe to cmd interface to run mongoDB command
It will show something like this:-

MongoDB shell version: 2.4.10
Connection to: test
>

Here you can write the command for MongoDB
1) First of all you need to create a database in mongodb

Run this command: use yourdb
The command will create a new database, if it doesn't exist otherwise it will return the existing database.

After that run this command db press enter then write your DBname name
expample:
use mydb
db
mydb

The db will now show until you will not add at least a collection in  database
So to insert the collection into the database you need run this command
db.createCollection("mycollection", options)

 Press enter

Now you can check via this command that is you database and collection created or not

show dbs

2) To check all database name, you need to enter this command
show dbs

Result:
 laravel 0.2.3125GB
Twitter 0.2.3556GB
Testdb  0.2.3245GB

3) Now you need to switch  databsae which one you want to use
use dbname

Result:
switched to db dbname

4) Now if you want to check the collection of database - run this command
show collections

Result:
system.indexes
user
comment
link
Post

5) To delete a database

first switched a database which you have already created

use dbname

Now write this command to delete the selected database. 
Please keep in mind before deleting any database switched the current database

db.dropDatabase()

Example: 

>use mydb

switched to db mydb

>db.dropDatabase()

>{ "dropped" : "mydb", "ok" : 1 }

> 

6)  To create the collection inside the database

Use this command: 

use dbname

db.createCollection("mycollection", options)

Options parameter is optional for size and capped value so 
leave it if you do not know about these parameter

7) To insert data into a collection

db.twitter.insert({"title":"mongotest"})

8) To drop collection from database

db.COLLECTION_NAME.drop()

Example:

First, check the available collections into your database mydb

>use mydb

switched to db mydb

>show collections

mycol

mycollection

system.indexes

tutorialspoint

> 

Now drop the collection with the name mycollection

>db.mycollection.drop()

true

> 

Again check the list of collections into database

>show collections

mycol

system.indexes

tutorialspoint

> 

9)  Get the data from collection

db.COLLECTION_NAME.find()

This will show data as a text on your cmd which is not formatted to read

If you want show data in formatted manner you can run this command too

>db.COLLECTION_NAME.find().pretty()

OR in MongoDB

Syntax:

To query documents based on the OR condition, you need to use $or keyword. Basic syntax of OR is shown below:

>db.mycol.find(

   {

      $or: [

                         {key1: value1}, {key2:value2}

      ]

   }

).pretty()

Using Like, AND and OR together

Example

Below given example will show the documents that have likes greater than 100 and whose title is either 'MongoDB Overview' or by is 'tutorials point'. Equivalent sql where clause is 'where likes>10 AND (by = 'tutorials point' OR title = 'MongoDB Overview')'

>db.mycol.find("likes": {$gt:10}, $or: [{"by": "tutorials point"}, {"title": "MongoDB Overview"}] }).pretty()

 Syntax to update the query: 

db.collection.update(   <query>,   <update>,   

 {     upsert: <boolean>,     multi: <boolean>,     writeConcern: <document>   }) 

To update the record

db.collection.update({"name":"TOM"}, {$set:{"count":500}}) 

TO update the record  

$set - WE use this keyword to set the new value and replace the last value 

if value not found then it create new field to that row

db.products.update( { sku: "abc123" },  

{ $inc: { quantity: 5 } } ) 

 $inc - We use this keyword to increment to that field which is mention in $inc keyword

Like: { $inc: { quantity: 5 } }  

so now it will add 5 in quantity likeif quantity was 2 then its value will be now 7. 

it works for both + and - the increment like: 

Like: { $inc: { quantity: -2 } }   

db.mycollection.remove() - To delete the all record from collection or empty the collection  

 Set Limit in collection:

 db.mycol.find().limit(1).skip(1)  

Sorting the record:  

db.COLLECTION_NAME.find().sort({name:1})

1 for ascending order-1 for descending order To get the backup of MongoDB database and server

mongodump 

Db.user.save(varibale):
Example: you can set a variable with its value before and later you can pass them
books = {"name":"sagar","class":"mongo"}
db.user.save(books)
Indexing: db.user.ensureIndex({name:1})

Multi Key index
db.user.ensureIndex({name:1})

db.user.ensureIndex({title:1}) 

OverView of MongoDB Tutorial:

use yourdb - To create DB or switched to DB

db.createCollection("mycollection", options) - To create collection

show dbs - To
 display all database
show collections - To display all collection from  a database

db.dropDatabase() - To drop the current database
db.createCollection("twitter ", options) - To create the collection inside the db
db.twitter.insert({"title":"mongotest"}) - To insert the data in collection

db.COLLECTION_NAME.drop() - To drop a collection from databae

db.COLLECTION_NAME.find() - To display the data from collection without formatted manner
db.COLLECTION_NAME.find().pretty() - To display the data from collection in formatted manner