Saturday, February 16, 2013

RDBMS Concepts & Interview Questions


1. What is a Database?
A database is a logically coherent collection of data with some inherent meaning, representing some aspect of real world and which is designed, built and populated with data for a specific purpose.

2. What is DBMS?
It is a collection of programs that enables user to create and maintain a database. In other words it is general-purpose software that provides the users with the processes of defining, constructing and manipulating the database for various applications.

3. What is a Database system?
The database and DBMS software together is called as Database system.

4. Advantages of DBMS?
Redundancy is controlled. Unauthorized access is restricted. Providing multiple user interfaces. Enforcing integrity constraints. Providing backup and recovery.

5. Disadvantage in File Processing System?
• Data redundancy & inconsistency.  
• Difficult in accessing data.  
• Data isolation.  
• Data integrity.  
• Concurrent access is not possible.  
• Security Problems.

Top 10 free cool games for Windows 8

The mighty Microsoft proved again why Windows is most used operating system. It has came up with attractive new user interface of tiles and added multiple features in style. Some of them are integration of various online Microsoft services and enhancement of Windows features. One of the interesting feature is integration of Xbox to Windows 8. Users can play Xbox games in their systems by signing in their Microsoft account which can be commonly used for all Microsoft services like Xbox, Bing, Outlook and Skype. Here I will show you some must play HD free games to improve your entertainment level. You can install all this games and more at Windows store.


1. Hangman HD

Classic paper game comes alive with 11 categories to play with. You can choose your skill level and category from Basic English, Advanced English, Animals, Famous People, Movies, World Countries, Body Parts, Foods, Occupations, Video Games and Unbeatable Hangman Words.


2. Archery Master

Archery games which provides you 20 arrows to play. Hitting the center will give you maximum i.e. 50 points and an extra arrow.


3. Jetpack Joyride

Loaded with gadgets and vehicles to play. The aim of the game is to fly maximum distance. Levels will be passed as the challenges are accomplished.


4. Air Hockey

The table game is virtualized well. Provides you option to play with computer and other player which will require a joystick.


5. Dredd v/s Zombies

Judge Dredd is on mission. Help him fight against Zombies. Cool game to play. It gives you customizable guns. Various levels and arenas are provided.


6. Chess 4 All

Give some exercise to your brain muscles. You can play this game online, single player and two player.


7. Microsoft Solitaire Collection

All 5 types i.e. Klondike, Spider, FreeCell, Pyramid and TriPeaks of solitaire card games are grouped together. Loaded with nice themes and daily challenges. Help is provided to let you learn to play these games.


8. Microsoft Pinball Fx

Classic pinball turns 3D and HD. You can unlock new stages by scoring high.


9. Rat on a scooter XL

Simple game to have fun with. The objective is to jump to stay on a bridge and collect as many cheese and coins as you can before falling.


10. Tic Tac Toe

Wintage Tic Tac Toe turns HD. You can play against computer and other player.


KnowCrazy.com Logos : How to make an effective logo

How to open a blocked website?

The most corrupted Indian government is making people frustrate. They are increasing the panic level of users by controlling Internet. The Internet addicts like me are highly affected and we have reached at peak of our capacity to bear the restriction on Internet which is meant to be open and free to all. Department of Telecommunication (DoT) is adding more sites everyday to block-list and its getting worse for everyone to use it as Internet is a primary requirement now-a-days. In this article I will help you dealing with sites blocked by your ISP so that you can have your right of availability of Internet. Lets get started. If you want to find a solution then you first need to understand the problem deeply. First I will tell you how the sites are blocked and then the solution will be given.

How the sites are blocked by ISP?

The process of blocking content for an ISP (Internet Service Provider) is very simple. After all, any content that is coming from a website to your computer has to travel through the ISP, giving it ample opportunity to observe and censor banned content. Think of it like this—you’re on an island, with no way to reach the mainland (Internet) where all the websites are. The ISP builds a bridge connecting you to the mainland, and charges you to let cars (data) from the sites come to you, by opening the road. Each web page has a unique ID, like a license plate. If the government tells the ISP to block a specific page, it’s added to the blacklist, and isn’t allowed on the bridge. The government could also block a full domain, such as Facebook.com, which would be like blocking all cars with DL plates, instead of specific numbers.

How to visit blocked sites?

Here we go. The solution to the problem is very simple. When you make a request to access a website by opening the URL (web address) in your browser, it tells the server to send that data to you. The data is sent to you by your IP address, which is provided by your ISP and is unique for everyone. So the accessibility of a website depends upon checking your IP whether in your region that site is permitted or not. So if you want to visit a blocked site then all you need to do is change your IP address to that one where that site is allowed. But it is not easy to change your IP as it is dynamically control by your ISP and you can only have variants of same network address which will ultimately represent your region. So does it mean that there is no solution and we can only access banned sites by changing our region? Well No! There is another way. That is called proxy.

What is a proxy server?

During a HTTP connection, the IP address of the client machine is necessarily transmitted in order to get the information back. This allows a server to identify the source of the web request. Any resource you access can gather personal information about you through your unique IP address - your ID in the Internet. They can monitor your reading interests, spy upon you and log your requests for third parties. Also, owners of the Internet resources may impose some restrictions on users from certain countries or geographical regions. An anonymous proxy server acts as a middleman between your browser and an end server. Instead of contacting the end server directly to get a web page, the browser contacts the proxy server, which forwards the request on to the end server. So an anonymous proxy server can protect your identity by stripping a request of all identifying information.

How do I use a proxy server?

There are a many online anonymous free proxy servers available using which you can access a blocked site in your region. Some of my favorites are Hide my ass and Zend 2. You can also google it to discover proxy sites. You can also install some plugins and extensions provided by proxy sites which will help you to have quick access. OK then here I am completing my article, I hope it helped you to increase your knowledge and you found a satisfactory solution. Feel free to share it with your friends and spread the word to help them out! For further queries you may contact me on Facebook, Twitter, Skype, Google+, Yahoo and also Email me. Enjoy!!.. :D