Top 30 OOPS Interview Questions And Answers

Q1. What is a class ?

ANS : A class is simply a representation of a type of object it is the blueprint slash plan slash template that described the details of an object

 

Q2. What is an object ?

ANS : Object is termed as an instance of a class and it has its own State behavior and identity

 

Q3. What is encapsulation ?

ANS : Encapsulation is an attribute of an object and it contains all data which is hidden that hidden data can be restricted to the members of that class levels are public protected private internal and protected 

 

Q4. What is polymorphism ?

ANS : Polymorphism is nothing but assigning behavior or value in a subclass to something that was already declared in the main class simply polymorphism takes more than one form 

Q5. What is inheritance ?

ANS : Inheritance is a concept where one class shares the structure and behavior defined in another class if inheritance applied on one class is called single inheritance and if it depends on multiple classes then it is called multiple inheritance none

 

Q6. What are manipulators ?

ANS : Manipulators are the functions which can be used in conjunction with the insertion and extraction operators on an object

 

Q7. Define a constructor ?

ANS : Constructor is a method used to initialize the state of an object and it gets invoked at the time of object creation rules for constructor , name should be same as class name constructor must have no return type

 

Q8. What is in line function ?

ANS : Inline function is a technique used by the compilers and instructs to insert complete body of the function wherever that function is used in the program source code

 

Q9. What is a virtual function ?

ANS : Virtual function is a member function of class and its functionality can be overridden in its derived class this function can be implemented by using a keyword called virtual and it can be given during function declaration virtual function can be achieved in C++ and it can be achieved in C language by using function pointers or pointers to function

 

Q10. What is friend function ?

ANS : Friend function is a friend of a class that is allowed to access to public private or protected data in that same class if the function is defined outside the class cannot access such information friend can be declared anywhere in the class declaration and it cannot be effected by access control keywords like private public or protected

 

Q11. What is function overloading ?

ANS : Function overloading is defined as a normal function but it has the ability to perform different tasks it allows creation of several methods with the same name which differ from each other by type of input and output of the function 

 

Q12. What is operator overloading ?

ANS : Operator overloading is a function where different operators are applied and depends on the arguments operator asterisk can be used to pass through the function and it has their own proceedings to execute sixteen what is an abstract class an abstract class is a class which cannot be instantiated creation of an object is not possible with abstract class but it can be inherited an abstract class can contain only abstract method Java allows only abstract method in abstract class while for other language it allows non abstract method as well

 

Q13. What is a ternary operator ?

ANS : Ternary operator is said to be an operator which takes three arguments arguments and results are of different data types and it is depends on the function ternary operator is also called as conditional operator 

 

Q14. What is the use of finalize method ?

ANS : Finalize method helps to perform cleanup operations on the resources which are not currently used finalize method is protected and it is accessible only through this class or by a derived class

 

Q15 What are different types of arguments ?

ANS : A parameter is a variable used during the declaration of the function or subroutine and arguments are passed to the function and it should match with the parameter defined there are two types of arguments called by value value passed will get modified only inside the function and it returns the same value whatever it is passed it into the function call by reference value passed will get modified in both inside and outside the functions and it returns the same or different value

 

Q16. What is super keyword ?

ANS : Super keyword is used to invoke overridden method which overrides one of its superclass methods this keyword allows to access overridden methods and also to access hidden members of the superclass it also forwards a call from a constructor to a constructor in the superclass

 

Q17. What is method overriding ?

ANS : Method overriding is a feature that allows subclass to provide implementation of a method that is already defined in the main class this will overrides the implementation in the superclass by providing the same method name same parameter and same return type - what is an interface an interface is a collection of abstract method if the class implements an inheritance and then thereby inherits all the abstract methods of an interface

 

Q18. What is exception handling ?

ANS : Exception is an event that occurs during the execution of a program exceptions can be of any type runtime exception error exceptions those exceptions are handled properly through exception handling mechanism like try catch and throw keywords 

Q19. What are tokens ?

ANS : Token is recognized by a compiler and it cannot be broken down into component elements keywords identifiers constants string literals and operators are examples of tokens even punctuation characters are also considered as tokens brackets commas braces and parentheses

 

Q20. Difference between overloading and overriding ?

ANS : Overloading is static binding whereas overriding is dynamic binding overloading is nothing but the same method with different arguments and it may or may not return the same value in the same class itself overriding is the same method names with same arguments and return types associates with the class and its child class

 

Q21. Difference between class and an object ?

ANS : An object is an instance of a class objects hold any information but classes don't have any information definition of properties and functions can be done at class and can be used by the object class can have subclasses and an object doesn't have sub objects

 

Q22. What is an abstraction ?

ANS : Abstraction is a good feature of hoops and it shows only the necessary details to the client of an object means it shows only necessary details for an object not the inner details of an object example when you want to switch on television it not necessary to show all the functions of TV whatever is required to switch on TV 

Q23. What are access modifiers ?

ANS : Access modifiers determine the scope of the method or variables that can be accessed from other various objects or classes there are five types of access modifiers and they are as follows private protected public friend protected friend

 

Q24. What is sealed modifiers ?

ANS : Sealed modifiers are the access modifiers where it cannot be inherited by the methods sealed modifiers can also be applied to properties events and methods this modifier cannot be applied to static members thirty how can we call the base method without creating an instance yes it is possible to call the base method without creating an instance and that method should be static method doing inheritance from that class you space key word from derived class

 

Q25.  What is the difference between new and override ?

ANS : The new modifier instructs the compiler to use the new implementation instead of the base class function whereas override modifier helps to override the base class function - what are the various types of constructors there are three various types of constructors and they are as follows default constructor with no parameters parametric constructor with parameters create a new instance of a class and also passing arguments simultaneously copy constructor which creates a new object as a copy of an existing object 

Q26. What is early and late binding ?

ANS : Early binding refers to assignment of values to variables during design time whereas late binding refers to assignment of values to variables during runtime thirty-four what is this pointer this pointer refers to the current object of a class this keyword is used as a pointer which differentiates between the current object with the global object 

 

Q27. What is the difference between structure and a class ?

ANS : Structure default access type is public but class access type is private a structure is used for grouping data whereas class can be used for grouping data and methods structures are exclusively used for data and it doesn't require strict validation but classes are used to encapsulate inherit data which requires strict validation

 

Q28. What is the default access modifier ?

ANS : In a class the default access modifier of a class is private by default share in your social networks and messengers

 

Q29. What is pure virtual function ?

ANS : A pure virtual function is a function which can be overridden in the derived class but cannot be defined a virtual function can be declared as pure by using the operator equals zero

 

Q30 What is dynamic or runtime polymorphism ?

ANS : Dynamic or runtime polymorphism is also known as method overriding in which call to an overridden function is resolved during runtime not at the compile time it means having two or more methods with the same name same signature but with different implementation 

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Top 25 HR Interview Questions And Answers For Freshers

Q1. Tell me about yourself or why don't you introduce yourself ?

ANS : Good morning first of all I would like to thank you for giving me such a great opportunity to introduce myself let me start with my educational background I graduated from Jayanthi University B in computer science and engineering after that I post to graduated from Osmani University M take in computer science and earlier I will adds my strengths and weaknesses I am always being self-starter hardworking person and would like to find new things to improve my skills or new technologies in general on my free time I play computer games and solving computer puzzles I like being with people in helping and I enjoy problem solving and challenging work and that is almost all about myself 

Q2. Tell me your strengths ? 

ANS : My greatest strength is persistency and consistency creativity quick thinking and good at decision-making I am always being self-starter self-motivated person hardworking person and would like to find new things to improve my skills on new technologies I am dedicated towards my work to achieve my personal and professional goals 

Q3. Could you please tell me your greatest weakness ?

ANS : I have some minor weaknesses a human being I am a little sense to I trust people very easily I'll definitely work on these in a war a bit of time in future I would like to be very honest and everything can at you in the right manner I don't like to say lies for the sake of any short-term benefits 

Q4. Tell me about your hobbies and interest ?

ANS : I love learning about new things I love crawling and made spend time with friends and family members I love playing computer games on my free time 

Q5. Can you work under pressure ?

ANS : I am not aware of any situation of pressure in office environment pressure reduced state of mind so I never feel such a pressure which effects on my work and when I feel any pressure I do just relax myself by doing some meditation or yoga moreover pressure is integral part of any job either it is hard or subject but I'll definitely do my best to avoid any pressure which is caused from my side 

Q6. Do you get angry if so how do you come out normal ?

ANS : I am a cool minded person and I am very positive person I don't get angry very easily but as a human being emotions are quite natural sometimes in some situation even without my mistake makes some angry and try to come out normal in a very short time by doing some meditations 

Q7. In some situations like fire what will you do ?

ANS : First of all I'll try to be emotional balance to avoid getting stress scale and then I'll check all fiery cheap places to take my safety and try to inform people around me and it is same time I'll try to inform Fire Department in office and try to help a your hand to others to come out all of them from this subnormal scenario 

Q8. What will you do if you are offered a job with a salary ?

ANS : I would like to start and build my professional career in the right direction so now I'll concentrate on my career building and growth so I'm not that much inclination interest towards money Eddie STIs 

Q9. What is more important to you money or success or job satisfaction ? 

ANS : Yet the money and success both are very important for me but I just have started my career so I enjoy and feel success with my job satisfaction know the reason behind this choice is if I am a successful person automatically money would follows often 

Q10. Would you lie for the company ?

ANS : I like to be very honest I don't like to say lies for the sake of any short-term benefits suppose if others knows that I lied for this company that moment that day it would give very bad impression and at the same time it may give negative impact and spoil my long-term career so I don't like this and now whenever if I am NOT a confident I will go for a lies  

Q11. How long you commit to work with us ?

ANS : I am looking my career in the right organization where I can grow both the personal and professional I want to learn and build my skills on many areas like technologies and communication as long as I am satisfied with all these new learnings and challenges from your automation I don't mind to change any other organization for the sake of any short-term any other benefits 

Q12. What motivates you at work ?

ANS : Many things are motivated me in my entire life in all phases as I told you earlier third time and self-motivated person and most of the time I love reading books on great people I learned many things from the great people so I inspire and motivate a lot from all these many books and great people 

Q13. Where you inspired in your life and why the my inspiration is my father always ? 

ANS : Since I have grown by observing and learning values from him in my life my father succeeded by his sword work and as being very honest he teaches me always how to lead a life in the right way as being very honest he has given me the best in my life in all aspects so my inspiration definitely would be my father 

Q14. How you would be an asset to this organization ?

ANS : As per my knowledge the growth of any organization is depends on collective effort I plan to have improve my abilities and become the leader in my field this means that I can contribute more to my employer and company so I will dedicate my work and play you missed from my side to the ordination growth and adding some values to the ordination so definitely I can say that I'll be part of this ordination and I have plans for long term and I will be a good asset to this ordination 

Q15. What is the difference between hard work and smart work 

ANS : Hard work and smart work are interrelated it almost all depends on each other if one works very on at initial stages then you would be a smart worker an initial basis of any hard work gives us good amount of knowledge and wisdom which would give us to take the right decisions at the right time that makes that give impression as to others we are the smart workers

 

Q16. Are you willing to relocate or travel ?

ANS : Yes I am very much flexible and I'm ready to travel to another location the next question would be are you willing to work on another technology when it requests again this is another flexibility related question yes I am flexible to work on other technologies but if you provide a professional training are good and give some enough time to Lane I'll definitely would like to walk on another technologies I do not mind to expand my technical skills as long as there is a growth which improves my career
 

Q17. Would you like to work some repetative work ?

ANS : Being a fresher I am not aware of how the reputation in the offices in the projects but in general I would like to learn new things and allowed to walk on creativity side and research kind of folk I know that it may not be possible in all scenarios all situations and all the times so I am fine to work with non repetitive in a short period but in long period I really don't like to work on repetition for a long time

 

Q18. Can you work independently ? 

ANS : I would like to work as a team and I'm a good team player but if I'm required to work independently as per the project requirement I will definitely open and flexible would like to walk on both environments I'd really don't mind

 

Q19. How do you evaluate your own performance ?

ANS : Generally I will evaluate myself periodically where exactly I am standing now if I really see a problem with my own performance I'll try to find out the root cause of the problem and I will go through all the situations where I'm in lack and I try to walk on each area and rectify them and I will try to come out into the normal situation to compete with with this old

 

Q20. What are your career options ?

ANS : As I am a pressure so now I am looking for a good break where I can store and build my career in the right direction and my career objective and goal or would like to be very successful both personal professional life in the right direction as being very honest so I would like to start my initial carrier from your ordination if I really get the opportunity I really like to join this ordination

 

Q21. Assuming that if you are selected what will be your strategy for next 60 days ?

ANS : If I really select for this position I will make sure to use each and every opportunity which are providing better by this ordination to build my starting career at the same time I will try to understand or making visions visions and values projects and technologies. I will give my best to put all my full efforts carefully and a contribute to the organization business and at the same time I will try to increase the overall profitability of the organization as much as possible from my set that means I will try to add some values to my career and my personal growth at the same time I will put some values to all nation Ruth is Ville

 

Q22. Where you see yourself after five years from now ?

ANS : Definitely I can see myself as being responsible person in this organization having great roles and responsibilities so definitely I can say that I will be I will be associating this organization long term and I will be a good asset to this organization I am sure that this organization can provide such opportunity such a growth to my career

 

Q23. What do you know about us and what do you know about the company ?

ANS : I have gone through our campaign website before attending this interview and and and I came to know that this ordination is providing opportunities to both freshers and experienced guys and also seen that how latest technologies are being used on both product and service and defend term projects on different domains and also gone through clients water water claims for this organization so I am quite interesting about this ordination and I am looking forward to start my career

Q24. How much salary do you expect so what is the cities you are expecting from this ordination ?

ANS : As I am a pressure I am not thinking about salary now I would like to I want to build my stock carrier with the right ordination we where deal you good amount of growth provide good amount of growth so I am going as for the company standing I really don't have any such figures in my mind 

Q25. Would you like to ask anything or do you have any questions to ask me ?

ANS : Yes I would like to know few things how long would be the training period and are there any provision affiliate and what are the office timings and our company providing any transportation facilities to the M price are there any additional benefit support from regular celery and I would like to know how soon I can join this ordination and thank you very much really

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Top 17 Web Developer Interview Questions And Answers

Q1. What is the importance of doctype in HTML ?

ANS : Doctype tells the browser which version of HTML xhtml standard is used and how to render the page

 

Q2. What is the difference between display:none and visibility:hidden ?

ANS : Display:none removes the element from the flow allowing other elements to fill in visibility:hidden only hides the element but space is allocated for it 

 

Q3. What is the difference between session storage and local storage ?

ANS : Session storage is available only when a browsers tab is opened local storage survives and closing and reopening a browser 

Q4. What are data attributes ?

ANS : Data attributes are used to store custom data directly inside HTML tags they are easily accessible from CSS and the JavaScript

 

Q5. Explain the difference between normalized CSS and reset CSS ?

ANS : Resetting removes all the native styles provided by browsers normalizing is just a correction of some common buds for example sub and sub elements will work as usual after normalizing resetting would make them look like plain text

 

Q6. What are sprites what is their purpose CSS ? 

ANS : Sprite is merging multiple images into a single image it reduces the amount of web requests and increases this page of speed

 

Q7. What is SVG ?

ANS : SVG stands for scalable vector graphics it is used to show vector graphics on the page the biggest benefit is that SVG images don't lose quality when zoomed or resized unlike JPEGs you can easily change the size color and animate SVG images SVG's also can be bundled in SVG sprite

 

Q8. What are the new features of html 5 ? 

ANS : Standard html 5 added new semantic elements such as NAV article section header footer and aside also html 5 standard added new form controls such our calendar date/time email URL and search in addition better support for embedded media using audio/video and canvas 

Q9. What is a CSS preprocessor ?

ANS : CSS preprocessor is a tool which allows you to create CSS code much faster in a more structured manner preprocessors extend the CSS functional by adding variables mix-ins partials also allow the use operation 

 

Q10. What is microdata ?

ANS : Microdata is a set of additional HTML tags for specifying the additional semantic information to help the search engines read your site properly

 

Q11. What tags are used to make a table ?

ANS : Table tag is used for wrapping a table th tag represents of the table heading TR tag creates a table row that stores the data elements the TD tag represents column in a row

 

Q12. What is the CSS box model ?

ANS : Box model represents a structured way to space elements in relationship to each other it is made of margins borders padding and content when the page is being rendered the browser shows each of the elements as rectangular which can be styled using CSS

 

Q13. What is the reason for wrapping the entire content of JavaScript ?

ANS : Source file into a function this is one of the best practices which creates a private namespace and thereby helps avoid potential name conflicts between different JavaScript functions and external libraries

 

Q14. How would you inspect a hover state of an element ?

ANS : In the dev tools to open it click the small colon hov text in the top right corner of the Styles pane 

Q15. How would you edit HTML in the dev tools ?

ANS : Right click on the text you want to edit on the HTML pane choose edit as HTML make your changes and press Enter

 

Q16. What is the difference between n quotes double equals and in quotes triple equals ? 

ANS : Operators in JavaScript the in-crowd triple equals operator behaves identically to the Equality of in quotes double equals operator but more strictly the types must be the same to be considered equal

 

Q17. What kind of loops are in JavaScript ?

ANS : Loop 4 goes through an inner code a number of times for /in used for looping through the properties of an object while goes through an inner code while a specified condition is true do forward slash while also goes through a block of code while a specified condition is true 

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TOP 20 Software Engineer Programming Interview Questions And Answers

Q1. What is 29 in binary and hexadecimal in binary ? 

ANS : it's 1 1 1 0 1 in hexadecimal it's 1d question number 

Q2. What is a singleton class ? 

ANS : A class that can only be instant paned once 

Q3. Explain inheritance in object-oriented programming ?

ANS : A class can inherit the implementation of its parent class while also extending and/or changing parts of it this allows for reuse of code that classes have a lot in common 

Q4. With threads a and B and resources x and y describe a deadlock situation ? 

ANS : Thread a Reserve's resource X then thread B Reserve's resource y thread a without releasing X then requests resource Y but have to wait for thread B to release it meanwhile thread B without releasing Y requests resource X but have to wait thread a to release it both threads are now waiting for each other to release their resources but none will until the other does 

Q5. What is a non functional requirement ?

ANS : A non functional requirement specifies general behavior requirements of the system it describes that you want your system to be rather than what it should do some non-functional requirements include accessibility maintainability and security 

Q6. What is a functional requirement ?

ANS : A functional requirement describes the specific functionality you want of your system 

 

Q7. What are steps of the waterfall ?

ANS : 1. Method requirements 

2. Design implementation 

3. Verification and maintenance

 

Q8. In scrum what is the purpose of the daily stand-up meeting ? 

ANS : The purpose of stand-up is for the team to get up to speed on what has been done and what will be done that day and to bring attention to real or potential obstacles in development the standard meaning works as follows each member of the development team answers three questions in turn one what did i do yesterday to what will I do today three have I discovered anything that might impede our progress towards the Sprint goal

 

Q9. What are the benefits and disadvantages of paper prototyping ? 

ANS : The main benefits of paper prototyping are that is quick and cheap and easily allows an entire team to take part in the design process disadvantages the major disadvantages is that it is hard to emulate the true field of the system and certain functionality such as scrolling data entry and dynamic elements often paper prototypes will only be able to show the general outline or show of a few specific functionalities of the system

 

Q10. What is the purpose of a sequence diagram and event diagram ?

ANS : A sequence diagram shows the interactions sent messages and return values between objects and in what order they are sent this gives an idea of the runtime flow of the application 

Q11. What is modularization ?

ANS : Modularization is a technique where the software is divided into several modules that work independently of each other the main benefit of this is better maintainability 

Q12. Can you describe the model-view-controller architecture ? 

ANS : The MVC architecture is used most commonly for GUI applications and means to separate the data from the user interface the model layer holds the data the view layout outputs the data to the user and the controller is responsible for making changes to the model based on user input 

Q13. What is direct graph ?

ANS : A cyclic graph ad a G is a directed graph without any cycles 

Q14. What is the difference between black box and white box testing ? 

ANS : White black box testing only tests a function for correct output given in an input white box testing also tests if the implementation is correct 

Q15. What is the difference between a queue and a stack ?

ANS : A queue is based on the FIFO first-in first-out principle which means the first item to enter the queue is the first to be removed like the queue at the cash register a stack on the other hand is based on the LIFO last in first out principle which means the last item to enter the stack is also the first to be removed like a stack of plates 

Q16. What is a recursive function ?

ANS : A recursive function is a function that calls itself and each function call one or more parameters are changed the recursion continues until a base case is reached and the recursion is result 

Q17. How does the a asterisks algorithm work ?

ANS : A asterisk is a path finding algorithm that works on weighted graphs with heuristic function that estimates the cost of traveling from node and to the goal node the notes to be considered at each step is stored in a collection usually a priority queue it starts by adding every node to the that is adjacent to the start node in the queue with their estimated total cost based on the formula F in parentheses n equals G in parentheses n plus h in parentheses and where G in parentheses end is the actual cost from the start node to the node and while h in parentheses n is the heuristic function at each iteration the node with the smallest estimates cost F in parentheses and is expanded a path is found when the goal node is the one chosen for expansion alternatively no path is found if the cube becomes empty 

Q18. In SQL with unique keys what does inner and outer join do ? 

ANS : Both operations join two tables inner join works as the intersection between the tables so only keys that exist in both tables will be kept in the joint table outer join works as the union between the tables so all rows are included in the joint table 

Q19. What is an SQL injection and how are they prevented ?

ANS : SQL injection is when SQL statements are entered into data fields that are to be stored in an SQL database the most usual mitigation techniques include parameterizing statements escaping characters with special meaning in SQL pattern checking and limiting database permissions

Q20. Why do you want to leave your current job? Why are you leaving your job and why do you want to work for us? 

ANS : I want to leave my job because I am looking for a fresh challenge with a company that has exciting and ambitious plans for the future, and one that will also use my skills and technical SQL abilities to the full. My employer has been great and we have achieved some fantastic things whilst I have been there, but I am now ready for a new challenge, and I would like that challenge to be with your company.

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Top 23 SQL Interview Questions Answers

 

Q1. What is SQL? 

ANS : “Structured Query Language, more commonly known as SQL, is seen as the standard for managing data kept in relational database management systems. For example, SQL statements are used to carry out tasks including updating the data, and also retrieving specific data from a database.” 

Q2. Why do you want to work for our company in this SQL position? 

ANS : “Within any SQL job, it’s really important to choose your employer carefully. What I mean by this is, in order to carry out your job properly, you need to work as part of a team that has clearly defined goals, sets high standards and also works collaboratively to achieve all company objectives. From what I found during my research into your organization, you are very well thought of by other people who work within the industry, you have exciting and ambitious plans for the future, and it is clear you give your staff the support they need to grow and develop within their roles.”

Q3. What is MySQL? 

ANS : “MySQL is an open-source relational database management system that is based on SQL, most commonly used for web databases. It was co-founded by Michael Widenius and the ‘My’ aspect of MySQL is the name of his daughter. The remainder is obviously an abbreviation for Structured Query Language. MySQL is utilized by a variety of database-driven web applications. These include WordPress and Joomla amongst others. It is also used by many of the world’s most popular websites, including YouTube, Facebook and Twitter. Written using C and C++ languages, MySQL supports the major platforms you’d expect such as macOS, Linux, and Windows.”

Q4. What's the main difference between SQL and MySQL? 

ANS : “So, SQL is often used to access, manipulate and update the data within a database, whereas MySQL is a relational database management system that keeps the data within the database organized. In other words, SQL is a language created to manage relational databases, and MySQL is an open-source relational database management system, based on SQL.” 

Q5.  In SQL, what are joins? 

ANS : “There are four main types of joins in SQL. These are FULL JOINS, RIGHT JOINS, LEFT JOINS and INNER JOINS. Joins basically combine the rows from two or more tables.” 

Q6. What is an index and why is it useful to have? 

ANS : “An index is useful because it allows for the faster retrieval of records from a table. The index creates an entry for each value, which in turn, makes it much faster to retrieve the data required, or in other words, an index is a pointer to data contained within a table.” 

Q7. If a constraint is added in SQL, what does this mean? 

ANS : “There are many different types of SQL constraints which can be used. Their purpose is to specify a rule for the data within a table, limiting the type of data that can go within the table. The constraint can be added either during the creation of a table, or once it has been created. Constraints can be applied to either the table as a whole or column level.” 

Q8. What are the more common types of SQL constraint and what do they mean? 

ANS : “There are several common SQL constraints. These are PRIMARY KEY, which identifies each record in a table; NOT NULL is used to prevent a NULL value being inserted into a column; FOREIGN KEY, which provides a unique identification of a row or record within another table; and also DEFAULT, which will automatically assign a default value if there has not been a value already specified for a field. There is also CHECK, which is a constraint that is used to verify that all values meet a specific criteria or condition in a field; and UNIQUE, which ensures unique values are always inserted into a column. Finally, INDEX is used to create data and to obtain it from a database with speed.”

 

Q9. So far, you have referred to tables and fields in your answers. What are they? 

ANS : “In its simplest form, a TABLE is a collection of data that is organized into rows and columns. The columns are vertical, and the rows are horizontal. The columns are called FIELDS and the rows are often referred to as records.” 

 

Q10. Tell me what the different subsets of SQL are? 

ANS : “So, there are three main subsets of SQL. Firstly, there is Data Control Language, or DCL, which permits you to control access to the database. For example, you can either grant access to the database or revoke it. Then there is DDL, which is Data Definition Language, which allows you to specify data structures in the database, including deleting tables, creating them or altering them. Finally, there is Data Manipulation Language (DML) which, as the name suggests, allows you to manipulate the data, including updating, inserting, deleting or retrieving data in the table as required.” 

Q11. How would you format SQL server dates? So, how would you format SQL server dates? 

ANS : “For this, the FORMAT function can be used. This function allows the formatting of the date and time. Firstly, I would decide what format I wanted, for example DD/MM/YYYY or MM-DD-YY. If I wanted to get DD/MM/YYYY I would use SELECT FORMAT (getdate(), 'dd/MM/yyyy’).” 

Q12. What is primary and foreign key? 

ANS : “For a database table to qualify as ‘relational’, it needs to have a primary key. A primary key has one or more columns. The data within the columns is then used to identify each row in a table. Basically, these are very similar to street addresses, for example. So, if you think of the rows in the table as the dustbins or trashcans belonging to houses on a street, the primary key is the list of the addresses. Primary key attributes cannot have NULL values. A foreign key is a column in one table. In that table, the values are members of a primary key column in another table. It is possible for a foreign key attribute to accept NULL values and for there to be more than one foreign key in a table.” 

Q13. What is database denormalization? 

ANS : “Denormalization is a method used to improve the performance of a database, allowing the retrieval of data in the quickest time possible. Essentially, the process of denormalization adds redundant database data into a table which in turn enables the performance of the database to improve significantly, as the same data can be put in several places.”

 

Q14. What is database normalization? 

ANS : “Normalization reduces redundancy of data within a database. Normalization is a design technique that places larger database tables into smaller tables and then uses specific relationships to link them. In other words, normalization is the process of putting each piece of data in the appropriate place, using multiple tables. The benefit is keeping data integrity and it makes updating faster, but retrieval of data, can then in turn be slower.”

 

Q15. In SQL, what is a subquery? 

ANS : “A subquery is often referred to as an inner query or inner select. As the name suggests, it is an SQL query nested inside a larger query, such as a SELECT, UPDATE, or INSERT statement, or indeed inside another subquery. A subquery can be used to retrieve data that will be used in the main query. This in turn provides a condition to restrict the retrieval of data even further.” 

Q16. What happens to the data rows in the table when the table contains a clustered index? What happens to the data rows in the table when the table contains a clustered index? 

ANS : “The data rows will be stored in order. Cluster indexes sort data rows based on their key values. When a table doesn’t use clustered index, this is called a heap – in other words, the data rows will be unordered.”  

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5 Steps to improve Programming Skills

5 Steps to improve Programming Skills

I have certain steps you can follow to improve your programming skills now. The first thing you need is a programming knowledge and of course right you must have started with any of the language maybe C C++ Java Python or JavaScript and you might be knowing the syntax of it because that's what we do so when you say you are learning a programming language the first thing you learn is a syntax now different languages have different syntax and that's why you know once you learn one language let's just see it is easier for you to learn C++ and then Java because they all follow this same syntactical paradigm another thing is once you have learned this syntax the next thing you have to follow these five steps so that you can work on your skills


FIRST STEP

-> Practice algorithms and data structures now when you learn a language you feel you know everything but that's not the case because when you learn the language you learn syntax

-> If you do if you want to implement it let's say if I give you a problem statement and you have to convert that problem statement into a code and your software it's not the act process first you have to convert that problem statement into a solution and that will be only steps

-> That's what we call it as algorithms and then we convert that algorithm into code now when I give you an example let's say if you want to if you want to find a given number is all or even I know in your brain somewhere doesn't acquire them

-> What you do is you convert that into a code right but if we talk about big problem statements so first you have to convert that into algorithms and you need practice for that and so for practicing that you have to solve some existing algorithms

-> You know if you open any algorithm book you have this searching and sorting techniques so you have to look for those things first so practice those algorithms and also data structures like we have linked list we have leased right

-> So practice all those things like we have trees so practice all those things together because so there are some algorithms which works with this this data structures so that will be a first step


SECOND STEP

-> When you learn a language and when you implement that in your own way so if I give a problem statement you will write your own code but sometimes the code which you write is not the correct way

-> Not saying it will not give you the right output but sometime what also important is the way you write a code the the compactness of your code the efficiency the speed efficiency

-> Is also a way of any code you heard about design patterns right now to improve those things what I would recommend is just see some other people's code and nowadays we have this huge repository called as github

-> In fact not just github we have different de filmed websites available as well but github is my favorite so what you can do is try to read other people's code because it might give you a new way of writing code

-> The same thing which you are writing but a different way like the syntax will remain same the the output will remain same but the way right up code will change

-> So what you will do is just go to github and as there are some places available just have a look on those things and the way them the moment you watch those could have you when you see those codes it will make an impact on your brain and next time you have code it will be helpful


THIRD STEP

-> The way I have improved my programming skills is by participating in the competition so when I was in my college I used to participate in multiple colleges or multiple college events

-> So may be coding event or debugging event or maybe aqueous events so initially I used to lose all those games but then later on I started winning

-> I was practicing it so initially of course you will lose because you don't know how to compete and later on the mall the more you compete the more

-> How exactly the cool now nowadays if you don't want to visit any qualities you can do it online so we have this thing called as company do programming's so if you can compete with people you know on different websites like hacker ranked hike on earth

-> We have code chef so just compete with people because they will so what happens is this website they will give you a problem statement and you have to convert that wrong statement in to a solution so of course have to write of cool

-> When normally when you submit your code maybe they will not accept it they will reject your code and that's where the lightning starts because initially you will get rejected

-> I got rejected multiple times and later on luckily one of my quad code selected that's without that what motivates you right so you have to participate in competitions

-> Because it will teach you how to code second it will teach you how to code efficiently and third it will teach you how to debug and that's very important in fact in the description area

-> You will find a link to an article and it will be helpful for you so just with the article it will help you to participate in computer programming


FOURTH STEP

-> It might sound weird but don't stick to one language explore try to explore more languages the thing is will we all we all love some languages

-> For example I love Java there are people who love Python then we'll have some people love PHP don't stick to one language because your language might be best but all the languages

-> They have some good things and some bad things or some shortcomings so when you learn another another language it will teach you a different way of idea code

-> For example when I learn Scala I learned about how do we you how do we do functional programming which helped me in my java language right so learn other languages because they have some extra features which you can implement in your language


FIFTH STEP

-> Why you learn a programming language at the end you want to build project so why not start building a project from start I'm not saying from day one but after learning a programming language

-> We have syntax and then implementing all these steps it's time to take time for you to build a project now it can be any project doesn't matter

-> Because we all have some passion right something else like some hobby may be you like to watch movie may be you like to read a book maybe I like playing games or maybe your photographer

-> What you can do is you can build a project for yourself so the first project should be for yourself example if you love music make a music player if you if you like games make your own game

-> Then that will be your first step because when you are doing for something for yourself you will feel good about it right and of course you will get stuck somewhere

-> Because this is your first project and there's multiple way you can solve this just go to Google and serve and but such for your problem and trust me Google knows everything right

-> We also have set for this type of flaw it will help you with the code ok don't just copy paste the code because that's what most people do try to understand the code

-> What they are saying try it out and try to customize it the way you want now don't just copy-paste it because it might lead to bugs and trust me bugs are harmful


Now after these five steps let me just repeat those steps :-

-> First one is practice algorithms and data structures
-> Second one is read other people's code
-> Third one is community programming
-> Fourth one is explore other languages
-> Fifth one is build a project now

With this I have a bonus step for you which is quite important because at least for me and that is keep following telescope it will surely help you to improve your programming skills.

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What is MVC (Model View Controller)

What is MVC (Model View Controller) 

-> This is not a new concept first of all and it is a thing that you see in your daily life as well I'll prove that in example just in a moment and also this is not specific to one programming language

-> It is a way of how you organize your code it is not like a specific thing for Ruby or PHP or for Java or for Swift it's just a way of how you organize your code and trust me you also see this kind of pattern every single day in your life

-> I can do a little bit better job in explaining what model-view-controller so yes you have seen model-view-controller probably a hundreds of time in your day-to-day life now

-> Let me try to explain what the model-view-controller is and where you see in your daily life so let's just see that this is you now you go to a restaurant and let's just assume this white entire animation kind of thing is a restaurant

-> You move on to a restaurant now what you do at a restaurant you don't just go to the kitchen and make a food by yourself you can do that at your home so what you wait you just go there and you wait for a waiter to come on now waiter comes to you

-> You just order the food to the waiter now waiter is not aware who you are or what you want to have it just gets that from you now whenever you sell the waiter that yes I want this the waiter just gets the order

-> Now waiter moves to the kitchen now in the kitchen waiter is not going to prepare your food, the food is prepared by the cook so let's bring up the cook now waiter will tell that the cook hey this is a guy out there

-> He wants this kind of food and now cook is the guy we're going to prepare the food for you but cook did not prepare the food magically he needs some ingredients to cook the food he'll open up the fridge

-> We'll put out something legitly you order an omelet so he'll get the egg sugar and whatever it needs so let's bring our fridge as well so now the fridge is there and cook will cook the food now cook

-> Will finally hand over the food to the waiter and probably the cook might hand over a couple of other foods as well like maybe a glass of soda or maybe my favorite icy or omelette that you have ordered now it's the job of the waiter to move those food outside the kitchen now waiter is actually aware

-> What kind of foods need to be served to you and how it should be served so waiters comes back to you and order and your order is now served so you might be wondering hey what this tool is all about and probably you might have anything guess that

-> This is all of your model-view-controller so this you guys is actually have you this waiter guy is actually the controller and yes you get that right this hood guy is model in itself and if you haven't guessed that yes the fridge guy is actually the data

-> So how about that this is a cool example and this is kind of a thing you see every day you have been going to restaurant every day and they are following a model-view-controller objectives throughout the year

-> So this is basically your model-view-controller now I can understand you have gone through with that restaurant example pretty easily and nicely now you want to understand how this is applied in the code

-> Now first of all a lot of people believe that model-view-controller is a thing for only dotnet or may be only for Ruby or may be hungry for PHP but it's not it's the design pattern it's the way how you arrange your code

-> It's going to be possible in everywhere you might want to write an application and PHP Swift java.net Ruby Python you can just arrange your code like that now the whole advantage of this approach is you can write dumb code

-> The more the code is going to be dumb it's going to be more beneficial what I mean by that now all I'm trying to say is we are trying to reduce the dependency of each code in this file from each other

-> We want that if some data is being passed on this file it just process this data it shouldn't be worried about from where this data is coming up ROM or there shouldn't be any dependencies

-> Wherever I does that I always recommend to use the model-view-controller approach but let me give you also an example that this kind of approach although is good in most places but in some places it can be opposite of that

-> Like for example if there is a store which just sells the popsicles or ice creams it would be really bad approach if we use model-view-controller there because there is just one job to do just bring up the ice cream from the fridge and serve it that's it if you use it if you will use the model-view-controller approach there

-> It would be overused and overkill of the resources so at some point of that time model-view-controller is not a good approach but in most of the cases where application is pretty humongous pretty big then it's a good idea to use the model-view-controller approach

-> Now although we are not going into the in depth of what this model what is view what is controller because if I will be taking an example specifically for Android it would be really not a good thing for iOS if I will be taking an example directly from iOS it would not be a good approach for Android

-> So all I'm doing here is trying to generalize the thing as much as possible now one thing I would like to mention that a lot of people misunderstood the thing that your model is not the data again

-> I repeat your model is not the data the data is completely separate it needs to be cooked up so that is what the cook is doing in our example

-> In the real life example your data would be something fetching up from an API request or maybe from the firebase or wherever you guys fetching your data and your models should be the guy who should cook up these data should process the data

-> Finally controller should be responsible from taking the data filtering the request and let us say you have asked for a result of maybe top 10 wonders of the world

-> There can be hundreds of such wonders of the world now you are looking only for the ancient wonder of the world so it's the job of controller to filter out the data and just produce that on to the view.

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