The tutorial provides the steps to insert document using MongoDB. A document is inserted in mongodb using insert() , insertOne() , insertMany() methods which we will discuss in detail with examples.
Insert Document in MongoDB
MongoDB stores the data into documents. The below points can be considered for the Insert Document in MongoDB
MongoDB allows to insert a single document in a collection
MongoDB allows to insert multiple documents in a collection
If the collection does not exist, MongoDB will automatically creates the collection
Each document in a collection requires a unique field (_id) which represents as the Primary Key for the document. MongoDB generates the ObjectId automatically if the _Id is not provided during the Insert Document
MongoDB ensures atomicity for the write operations
What is objectId in MongoDB ?
An ObjectId is :
An unique key or id
it is faster to generate
it has 12 bytes length ( 4 byte – timestamp for objectId creation, 5 byte – random value , 3 byte – incrementing counter)
ObjectId creation can be accessed by ObjectId.getTimestamp() method
The Insert Document Methods in MongoDB
Option 1: Insert Document
Syntax – db.collectionname.insert(document)
This command is the basic command to insert document where collectionname is the name of the collection, insert is the CRUD Operation for inserting single or multiple document. The below given is the sample for inserting document
The inserted record can be validated by the below find command. Although we had not provided the _Id ( unique value) for the inserted document, but MongoDB automatically creates the _id as given below.
Another example for insertOne() where _id is being provided. MongoDB considers the same _id and returns it back with the acknowledgement for the inserted document.
The tutorial provides the steps to create a collection and drop a collection using MongoDB. A collection is created in mongodb using createCollection()
Document: A document is single unit or data record similar to a row in RDBMS for storing information. A document is a JOSN object storing data in the form of key-value pairs.
Collection: A collection is a group of documents for storing data similar to RDBMS tables. MongoDB contains multiple collections in the database similar to RDBMS which contains multiple tables in the database
Create Collection in MongoDB
The MongoDB provides the method – db.createCollection(name, options) to create a collection.
Create Collection Syntax:
db.createCollection(name, options)
Where
name is the collection name
options is the document to specify collection configuration
Argument
Argument Type
Argument Description
Name
String
Name of the Collection
Options
Document
Optional. Configuration details like Memory Size, Indexing
capped
Boolean
Optional. Enables the Capped Collection which are fixed size collections. When reached max size (in bytes) , capped collection overwrites the old entries
autoIndexId
Boolean
Optional.
When enabled , creates index on _id field.
size
Number
Optional.
Used in Capped Collection . When enabled, specify max size in bytes
max
Number
Optional.
When Enabled, allows to specify max documents in the Capped Collection.
Lets execute a simple collection method call for creating the collection in MongoDB
> use oracleappshelpDB
switched to db oracleappshelpDB
> db.createCollection("oracleappsHelpBCollection")
{ "ok" : 1 }
The OK depicts that the collection – “oracleappsHelpBCollection” is created. We can verify by executing the show collections
> show collections
oracleappsHelpBCollection
>
Let’s execute create collection method with the Optional arguments
Core Java Array interview questions on the identification of multiple sub arrays within in the Array Input whose array elements sum is Zero.
Program Logic:
– Java Array provided with the list of array elements. * Traverse the elements to identify if the value of that element is zero. * Traverse the elements to identify if the value of multiple array elements sums up to Zero * Print each such occurrence as an sub-array
package core.java.oracleappshelp.array;
public class identifySubArrayInArrayWithSumZero {
// Function to print all sub-arrays with 0 sum present
// in the given array
public static void identifySubArrayToDisplay(int[] ArrayWithAllElements)
{
// Traverse for the sub- array through the outerLoop
for (int outerLoop = 0; outerLoop < ArrayWithAllElements.length; outerLoop++)
{
int sum = 0;
// Traverse for the sub- array through the innerLoop
for (int innerLoop = outerLoop; innerLoop < ArrayWithAllElements.length; innerLoop++)
{
// adding value for innerLoop and outerLoop to get total sum value.
sum += ArrayWithAllElements[innerLoop];
// validate if the array index for innerLoop and OuterLoop sums up to 0
if (sum == 0) {
System.out.println("Subarray [" + outerLoop + ".." + innerLoop + "]");
}
}
}
}
public static void main (String[] args)
{
int[] A = { -2, 2, 1, 5, -6, 3, 1, -4, };
identifySubArrayToDisplay(A);
}
}
The below java program executes the java method – sortArrayElementsInBinaryFormat( ) to sort the received list into the Binary format of 0s and 1s in sequence.
Program Logic:
1. Pass the Array Element List to the method – sortArrayElementsInBinaryFormat( )
2. Traverse and identify the elements with 0 value
3. Move the elements with 0 value forward and elements with value 1 thereafter
4. Print the sorted binary array
Array Input : { 1, 0, 1, 0, 1, 0, 1, 1, 1, 0, 0 }
Array Output: [0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1]
/*
* Java Array Program to sort the received Array Binary Input of 0 and 1
* identify the elements with 0 value
* Move the elements with 0 value forward in the Array
* elements with 1 value to be placed after all 0s
* Input : { 1, 0, 1, 0, 1, 0, 1, 1, 1, 0, 0 }
* Output: {0,0,0,0,0,1,1,1,1,1,1}
*/
package core.java.oracleappshelp.array;
import java.util.Arrays;
public class GenerateBinaryArray {
/* Method - sortArrayElementsInBinaryFormat
* Java Method to sort the received list into the Binary format of 0 and 1 in sequence.
*/
public static void sortArrayElementsInBinaryFormat(int[] arrayElements)
{
// identify the elements with 0 value
int elementWithZeroValue = 0;
for (int elementValue : arrayElements) {
if (elementValue == 0) {
elementWithZeroValue++;
}
}
// move the elements with 0 value forward and elements with value 1 thereafter
int elementLoop = 0;
while (elementWithZeroValue-- != 0) {
arrayElements[elementLoop++] = 0;
}
// fill all remaining elements by 1
while (elementLoop < arrayElements.length) {
arrayElements[elementLoop++] = 1;
}
}
// Sort binary array in linear time
public static void main (String[] args)
{
int[] arrayElementList = { 1, 0, 1, 0, 1, 0, 1, 1, 1, 0, 0 };
sortArrayElementsInBinaryFormat(arrayElementList);
// print the sorted binary array
System.out.println(Arrays.toString(arrayElementList));
}
}
Java Array Program Output:
[0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1]
How is an array different from ArrayList ? What are the major differences between Array and ArrayList ? Why difference between Array and ArrayList is the most commonly asked Java Interview Question . Below given are the points for Array vs ArrayList which describes it.
S. No
Array
ArrayList
1
Array is fixed length , thus static in nature
ArrayList is dynamic in nature
2
Array does not extend any class or implement interface
ArrayList implements the List Interface and internally backed by Array
3
Array does not support Generics and throws ArrayStoreException
ArrayList supports Generics and ensures type-safety.
4
Array provides length() method to calculate
the Array Length
Example:
int studentObject[] = new Integer[3];int int studentObjectLength= studentObject.length ;
ArrayList provides size() method to calculate the ArrayList size
Example: ArrayList studentObject = new ArrayList(); studentObject.add(101); studentObject.add(102); studentObject.size();
5
Arrays allows to store primitive types and objects
ArrayList allows to store objects only
6
Array uses assignment operator to store element into array
Example:
int[] studentId = { 101, 102,103,104,105 };
Object[] studentId = new Object[10];
ArrayList uses add() method to store element in ArrayList
Example:
ArrayList<Integer> studentIdList = new ArrayList<Integer>(); studentIdList.add(100);
7
Arrays are faster when frequent access is required.
Array operations execution time
Arrays Lookup – O(1)
Arrays Append ( last element) – O(1)
Array Insertion – O(n)
Array Deletion – O(n)
ArrayList is faster when frequent insert and deletion is required. Overall ArrayList takes more time as it uses List interface as part of Collection Framework and each node in the List has its own memory when compared to Arrays.
Java array is the most important and commonly asked topic in programming interview questions. The Tutorial shares the top 30 java array interview questions and answers for IT exam or interview preparation. Java Array is one of the used data structure in java programming and thus important for beginners and experienced programmers to possess clarity on java array implementation.
1. What is an Array in java ?
Java Array is the data structure with the collection of elements to organize and store the objects sequentially.
Array in java uses index for each position. Array Index starts from 0 position.
Array stores the collection of elements with the similar data types.
Array are fixed in length and thus not expandable in size.
Array objects in java are stored in the heap memory and not on the stack.
Arrays can be categorized as 1-dimensional array, 2 -dimensional array, N-dimensional array.
Arrays in java are implemented in other data structures like List, Heap, Hash Tables, Queues, Strings.
The simplest example of Array data structure could be a linear array (also called 1-dimensional array)
2. What are the advantages and disadvantages of array in java?
Advantages:
Arrays in java provides fast lookup (retrieval / traversal) of elements using index.
Array retrieval takes o(1) times irrespective of the array length
Appending array with new element at the end of the array works faster , takes O(1) time.
Disadvantages:
Arrays in java are of fixed length and thus cannot be expandable at run time.
Collection of elements in array should be of same data type.
Array insertion and Array deletion take O(n) time and thus makes the operation costlier with respect to execution time.
Below given are the Array operations and their execution time.
Array Operations
Array Execution Time
Array Space
O(n)
Array Lookup / Retrieval
O(1)
Array Append (last element)
O(1)
Array Insertion
O(n)
Array Deletion
O(n)
3. How the array is stored ?
Array is an object in the java and it is being stored in the heap memory in the JVM
4. Can the array be declared without size?
No. Array is fixed length in java and need to be initialized with size.
5. Does Array allows adding string value into Integer Array ?
We know that Arrays in java is the collection of elements with the same data type. Thus , storing string value in Integer Array gives the compile time error.
package core.java.oracleappshelp.array;
public class AssingStringToIntArray {
public static void main(String args[]) {
int[] assingIntValue = new int[5];
assingIntValue[0] = "Mohit"; //compile time error
}
}
6. Explain ArrayStoreException and hierarchy in Java Array ?
The ArrayStoreException exception occurs when the object is stored with a different data type which is not same as per the defined array object. Let’s consider another example. Create an Array of object assigned with String [ ] . Add the integer value. In this case, although compiler doesn’t give compile time error but it does generates ArrayStoreException at the run-time.
package core.java.oracleappshelp.array;
public class ArrayStoreExceptionExample {
public static void main(String[] args) {
Object[] students = new String[10];
students[0] ="Rohit";
students[1] ="Mohit";
// assignment of integer generates ArrayStoreException at run time.
students[2] = new Integer(0);
}
}
Program Output:
Exception in thread "main" java.lang.ArrayStoreException: java.lang.Integer
at core.java.oracleappshelp.array.ArrayStoreExceptionExample.main(ArrayStoreExceptionExample.java:8)
ArrayStoreException(): Constructs an ArrayStoreException instance with no detail message.
ArrayStoreException(String storeExcMessage): Constructs an ArrayStoreException instance with the specified message
7. What are the common errors / exceptions in Arrays ?
NullPointerException : when value accessed is retrieved as NULL at run-time.
NegativeArraySizeException when array is identified with a negative size
ArrayIndexOutOfBoundsException : When array is accessed or modified with a invalid index or index value is idnetiifed more than the array size.
ClassCastException :
package core.java.oracleappshelp.array;
public class ArrayClassCastExceptionExample {
public static void main(String[] args) {
Object storeIntValues = new Integer(10);
System.out.println((String)storeIntValues);
}
}
Program Output:
Exception in thread "main" java.lang.ClassCastException: java.lang.Integer cannot be cast to java.lang.String
at core.java.oracleappshelp.array.ArrayClassCastExceptionExample.main(ArrayClassCastExceptionExample.java:6)
ArrayStoreException: Refer the above question explained with the example.
8. What is the default array value for different data types ?
Java Data Type
Default Array Value
byte, short,int,long
0
float, double
0.0
boolean
false
Object
null
9. Is Generics use supported in array ?
No
10. Define anonymous array in java ?
The Array which does not have a name or reference is termed as anonymous array in java.
new String[]{“Open”, “Close”, “Save”};
new int[] {100,200,300,400,500};
11. What are jagged arrays in java ?
Arrays containing arrays with different size are termed as jagged arrays.
Example: Multi-dimensional arrays included Jagged arrays.
12. Can the array with higher size be assigned to an array with less size ?
Yes, arrays support this feature. If an array1 has size of 10 elements and array2 has size of 5 elements, then array1 can be assigned to array2 even though it has less element size as array validation checks for the array to be of same data type and does not validate on the array size during compilation.
import java.util.*;
public class CopyLargeArrayToSmallArraySize{
public static void main(String args[]) {
int[] arrayWithLessSize = new int[20];
int[] arrayWithLargeSize = new int[40];
arrayWithLessSize = arrayWithLargeSize;
System.out.println(arrayWithLessSize.length);
}
}
13. Write a java program to sort an array and print in java ?
The below java program uses Arrays.sort( ) method to sort the numbers in array
package core.java.oracleappshelp.array;
import java.util.Arrays;
public class arraySortingInJava {
public static void main(String[] args) {
int[] numberList = { 700, 100,500,900,50 };
Arrays.sort(numberList);
for (int traverseList : numberList)
System.out.print(traverseList +" ");
}
}
Array Program Output:
50 100 500 700 900
14. what are the possible ways to copy array content from one array to another ?
The below given methodologies can be applied in java for copy array content
Using for loop to traverse and copy the content
Using clone( ) method
Using Arrays.copyOf( ) method
Using System.arraycopy ( ) method
15. Describe the differences between Array and ArrayList ?
16. What will be the ouput for an Array which is not initialized ?
The Array will be assigned with the Default Value based on the Array Data Type
17. Write a java program to identify duplicate array elements in java ?
package core.java.oracleappshelp.array;
public class IdenitfyDuplicateArrayElements {
/* Method Name - getDuplciateArrayElements
* Java method to identify the duplicate array elements from the received any input.
*/
public static void getDuplciateArrayElements(String[] studentNames) {
for(int outerLoop=0; outerLoop < studentNames.length-1; outerLoop++){
for(int innerLoop=outerLoop+1; innerLoop < studentNames.length; innerLoop++) {
if(studentNames[outerLoop].equals(studentNames[innerLoop]) && outerLoop!=innerLoop ) {
System.out.println("Idneitifed duplicate array element is : "+ studentNames[innerLoop]);
}
}
}
}
public static void main(String args[]) {
String[] studentNames = {"Roit", "Mohit", "Vinay", "Mohit", "Akshay" };
getDuplciateArrayElements(studentNames);
}
}
18. Is an array thread-safe in java ?
Array operation is java have their complexity.
Array Retrieval is thread-safe.
Array insertion, updation and deletion are not thread-safe.
19. Can array be made volatile ?
Only variable representing an array can be made volatile
20. Write a java program to check if the given two arrays are equal or not ?
The below given program uses Arrays.equal( ) method to validate if the comparison of two arrays is equal or not.
package core.java.oracleappshelp.array;
import java.util.Arrays;
public class ArraysComparison {
public static void main(String[] args) {
int[] arrayObject_1 = { 700, 100,500,900,50 };
int[] arrayObject_2 = { 700, 100,500,900,50 };
int[] arrayObject_3 = { 100, 200,500,900,50 };
System.out.println(" Is Array Object 1 Equals to Array Object 3" + Arrays.equals(arrayObject_1 , arrayObject_2));
System.out.println(" Is Array Object 1 Equals to Array Object 3" + Arrays.equals(arrayObject_1 , arrayObject_3));
System.out.println(" Is Array Object 2 Equals to Array Object 3" + Arrays.equals(arrayObject_2 , arrayObject_3));
}
}
Array Program Output:
Is Array Object 1 Equals to Array Object 3 true
Is Array Object 1 Equals to Array Object 3 false
Is Array Object 2 Equals to Array Object 3 false
21. How many ways multi dimesional arrays can be created in java ?
Multi Dimesional arrays in java could be 2D, 3D and 4D . Below given are the few examples of creating multi dimesional arrays in different ways
/* 2 Dimesional Arrays */
int[][] twoDimesionalArray1;
int twoDimesionalArray2[][];
int[] twoDimesionalArray3[];
/* 3 Dimensional Arrays */
int[][][] threeDimesionalArray1;
int threeDimesionalArray2[][][];
int[] threeDimesionalArray3[][];
int[][] threeDimesionalArray4[];
/*4 Dimesional Arrays */
int[][][][] fourDimesionalArray1;
int fourDimesionalArray2[][][][];
int[] fourDimesionalArray3[][][];
int[][] fourDimesionalArray4[][];
int[][][] fourDimesionalArray5[];
22. How to convert an array to arrayList in java ?
The below apprach can be used for converting an array to arrayList in java
Using Arrays.asList() method
String studentNames[]={"Mohit", "Rohit", "Snehashish", "Akshay"};
/* Using Arrays.asList() method to convert array to ArrayList */
ArrayList<String> studentList= new ArrayList<String>(Arrays.asList(studentNames));
Using Collections.addAll() method
String studentNames[]={"Mohit", "Rohit", "Snehashish", "Akshay"};
/* Create ArrayList studentList*/
ArrayList studentList= new ArrayList();
/* Using Collections.addAll() method to convert array to ArrayList */
Collections.addAll(studentList, studentNames);
23. How to find the Second Largest Number in the Array in java ?
The below steps can be performed to identify the second largest array element in java
Intitialize the array with the array elements
Sort the Array by using Arrays.sort() method
The last Number is the Array is the largest number after sorting
Traverse the array elements from 0 to n-2
compare the array element with the last element in array
package core.java.oracleappshelp.array;
import java.util.Arrays;
public class SecondLargestNumInArray {
public static void main(String[] args)
{
int studentRollNo[] = new int[] {101,21,45,51,19,2};
// Call Arrays.sort() method
Arrays.sort(studentRollNo);
// Traverse the StudentRollNo Array till Second last element
for(int loop=0; loop < studentRollNo.length; loop++) {
// Print second last element
if(loop == studentRollNo.length- 2)
System.out.println(studentRollNo[loop]);
}
}
}
24. How to validate if a particular value exists in array object in java ?
We can utilise the below array method to get the value from array object
The java array program receives the list of unsorted array elements and sum value as input to the program. The array elements will be traversed and adds the sum of array elements at respective array index to compare if that equals to the sum value received as an input. If value matches at array index, the program will print the indexes else print “Array Element Pair not found”
Here , the index 1 and index 4 sum is equal to the given sum.
package core.java.oracleappshelp.array;
public class ArrayPairSumEqualToArraySum {
private static void findPair(int[] ArrayWithAllElements, int sum) {
{
// Traverse for Array Object till Array length -1
for (int outerLoop = 0; outerLoop < ArrayWithAllElements.length - 1; outerLoop++)
{
// Traverse for the InnerLoop till last element
for (int innerLoop = outerLoop + 1; innerLoop < ArrayWithAllElements.length; innerLoop++)
{
// check if the 2 compared elements sum is equal to the Array Sum
if (ArrayWithAllElements[outerLoop] + ArrayWithAllElements[innerLoop] == sum)
{
System.out.println("Element Pair found at index " + innerLoop + " and " + outerLoop);
return;
}
}
}
// When no array element is qualified
System.out.println("Array Element Pair not found");
}
}
public static void main (String[] args){
int[] ArrayObjList = { 2, 8, 4, 6, 12, 17 };
int ArrayTotal = 20;
findPair(ArrayObjList, ArrayTotal);
}
}
Array Program Output:
Element Pair found at index 4 and 1
The tutorial provides the steps and mongoDB shell command execution to create database in MongoDB, drop database in MongoDB , create and drop statements in MongoDB with examples.
The MongoDB provides the below given command to create the database. The command will create the New Database if doesn’t exist , else it returns the existing database. MongoDB uses default database as test for storing the documents if no database is created.
Syntax: use DATABASE_NAME
use oracleappshelpDB
switched to db oracleappshelpDB
Command to select the created database oracleappshelpDB
db
oracleappshelpDB
Command to get the list of all database in the MongoDB
show dbs
admin 0.000GB
config 0.000GB
local 0.000GB
The created database oracleappshelpDB is not listed as we need to have atleast 1 document to be inserted
The below given command can be used for dropping the database from MongoDB
db.dropDatabase()
As we are using oracleappshelpDB and inserted the document , thus current database in selection is oracleappshelpDB . If we execute the command db.dropDatabase() it will remove the database. In case of no specified database, the command will delete the default database “test”.
Execute the show dbs and use oracleappshelpDB command to switch to the required database which needs to be dropped.
show dbs
admin 0.000GB
config 0.000GB
local 0.000GB
oracleappshelpDB 0.000GB
> use oracleappshelpDB
switched to db oracleappshelpDB
Now, execute db.dropDatabase() command and then show dbs to ensure database is not shown now
> db.dropDatabase()
{ "dropped" : "oracleappshelpDB", "ok" : 1 }
> show dbs
admin 0.000GB
config 0.000GB
local 0.000GB
The tutorial provides the step by step process for installing MongoDB on windows 10.
Download MongoDB from community site: Click on the Download MongoDB link and get the on-premises installer from the community site (mongodb-win32-x86_64-2012plus-4.2.8-signed)
Download MongoDB
Start the installer: Click on the msi windows 64-bit installer ( mongodb-win32-x86_64-2012plus-4.2.8-signed ). Click Next and Accept the License Agreement Terms checkbox.
MongoDB Installer
Select Components: Click on “complete” button to install all the required MongoDB components.
Select MongoDB components
Service Configuration: Select option as “Run Service as a Network Service user” . Click Next.
MongoDB Service Configuration
Install MongoDB compass: Click Next to start the installation for MongoDB compass
MongoDB Installation Progress: The below screen shows the MongoDB installation progress.
MongoDB Installation progress
Click Finish when the installation is completed.
MongoDB compass is the non-commercial interactive GUI for managing the MongoDB Structure , querying the available data with the data representation.
Interactive editor for displaying document structure
Provides visual explain plans
Provides index management
Provides editing with validation of individual BSON types
Provides replica set connection to avoid fail over
Provides Query history
MongoDB compass provides the privacy setting to be enabled to provide various reports for MongoDB Data crash, MongoDB Data Statistics and MongoDB automatic updates.
MongoDB Compass Privacy Settings
Starting MongoDB in windows
As MongoDB generated documents , it requires the data folder to be specified to store its file. Create the data folder in C:/
C:\>md data
C:\md data\db
Now we need to provide this data folder location while running the MongoDB exe as given below
Ruby should be installed on the system as the prerequisite
Execute the below command to install Ruby driver for using MongoDB NoSQL Database
Install Java Driver for using MongoDB
The MongodB provides the 2 maven artifacts for using MongoDB with the java driver.
mongodb-driver-legacy driver:It is the synchronous legacy driver
Entry point – com.mongodb.MongoClient
Central classes – com.mongodb.DB, com. mongodb.DBCollection, and com.mongodb.DBCursor
mongodb-driver-sync driver: It is the synchronous Java driver which provides the generic MongoCollection interface that complies with a new cross-driver CRUD operations.
Module Name – org.mongodb.driver.sync.client
The mongodb-driver-sync artifact is a valid OSGi bundle whose symbolic name is org.mongodb.driver-sync
Dependency: Add the below dependency in Java application for using MongoDB driver
The blog discuss on the common topics like What is MongoDB NoSQL Database ? What is document-oriented database ? Why MongoDB NoSQL Database is preferred than traditional RDBMS Database ?
What is NoSQL Database ?
The IT applications were extensively using the Relational databases like Oracle, SQL Server, MySQL for storing and retrieving the data. But with the upcoming trend of mobile applications like Facebook, Twitter and increasing demand for online shopping, has changed the trend of how application were managing and updating the application and customer data. In Relational Database, we need to create schemas, table, Indexes , define attribute data types, etc for database operations like create, update and delete records.
NoSQL database doesn’t requires these operations as prerequisite and can be executed on the fly to create, update and delete records which makes it easier to use and provides high performance.
What is MongoDB Database?
The MongoDB database is a cross platform NoSQL document-oriented database used for high volume data storage. MongoDB is an open -source database developed by the company 10gen. MongoDB was released in March 2010.
Why MongoDB ?
The MongoDB being a document-oriented database where database is a physical container for collections (set of file in the file system) whereas RDBMS Database consider each table data as a storing element. A collection is a group of documents with different fields maintained in the database with no enforced schema. The documents in the collection maintains a key-value pair which makes it useful for storing dynamic data (storing field with different types and structure). The key-value pair in MongoDB helps in providing high performance and scalability. The below given are the MongoDB features:
MongoDB is schema -less as it is document-oriented database using collections for storing documents
MongoDB allows to store different fields with different content and size in the document
MongoDB avoids complex joins for retrieving the data
MongoDB provides dynamic query for document data retrieval
MongoDB is scalable
MongoDB provides high performance
MongoDB is easy to use
MongoDB is light weight
MongoDB is much faster when compared with Relational Databases
provides Auto-sharding for horizontal scalability
provides built in replication for high availability
Difference between RDBMS and MongoDB ?
RDBMS Database
MongoDB Database
Relational Database requires schema, table creation, indexes, define attribute types to create, update and delete records
MongoDB allows to create, update and delete records on the fly and does not require table structure.
RDBMS is a heavy weight Database
MongoDB is a light weight database
RDBMS uses table as storing elements
MongoDB uses collections for storing documents
RDBMS supports multiple schema
MongoDB stores dynamic data using documents and supports JSON format
The tutorial provides the hardware virtualization concepts, advantages of hardware virtualization in the cloud computing environment The tutorial is useful for both beginners and professionals.
What is hardware virtualization ?
The hardware virtualization is the mechanism through which multiple simulated environments or dedicated resources are shared from a single physical hardware . Hardware Virtualization can be achieved by installing HyperVisor as an abstraction layer between the software application and the physical hardware. HyperVisor creates isolated instances called as “Virtual machines” where each VM is installed with Operating System and Software Application to run independently without impacting other running VMs.
The hardware virtualization not only allows to install multiple applications on the single physical server but it alos allows to utilize the maximum physical server capacity which was underutilized on physical servers without virtualization. As each VM runs independently , it allows provided high server performance even though deployed with multiple applications.
Harware Virualization example: VMWare , Microsoft Hyper -V
Virtualization diagram
Advantages of Hardware Virtualization
Maximum utilization of server resources
Reduces the overall hardware cost
Provides highly orchestrated operations to ensure maximum uptime
