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How to Create Auto Incremented Identity Column in SQL Server, MySQL, and Oracle? Example

Automatic incremented ID, Sequence, or Identity columns are those columns in any table whose value is automatically incremented by database based upon predefined rule. Almost all databases e.g. Microsoft SQL Server, MySQL, Oracle or Sybase supports auto-incremented identity columns but in different ways like Oracle provides a SEQUENCE object which can be used to generate automatic numbers, Microsoft SQL Server up to 2008 version provides IDENTITY() functions for a similar purpose. Sybase also has IDENTITY function but little different than SQL Server and MySQL uses auto_incremented keyword to make any numeric column auto-incremented.

Top 10 Oracle Interview Question and Answer - Database and SQL

These are some interview questions and answers asked during my recent interview. Oracle interview questions are very important during any programming job interview. The interviewer always wants to check how comfortable we are with any database either we go for the Java developer position or C, C++  programmer position. So here I have discussed some basic questions related to the oracle database. Apart from these questions which are very specific to the Oracle database, you may find some general questions related to database fundamentals and SQL like Difference between correlated and noncorrelated subquery in database or truncate vs delete in SQL, etc.

Difference between close and deallocate cursor in SQL

Cursor in a database is used to retrieve data from the result set, mostly one row at a time. You can use Cursor to update records and perform an operation a row by row. Given its importance on SQL and Stored procedures, Cursor is also very popular in SQL interviews. One of the popular SQL questions on Cursor is close vs deallocate. Since both of them sounds to close the cursor, once the job is done, What is the real difference between close and deallocate of Cursor in SQL? Well, there is some subtle difference e.g. closing a cursor doesn't change its definition. In Sybase particular, you can reopen a closed cursor and when you reopen it, it creates a new cursor based upon the same SELECT query.

10 Examples of Stream Class in Java 8 [ map + filter+ flatmap + collect + findFirst ]

There is no doubt that Stream class is one of the most important class of Java SE 8 API and a solid knowledge of this class is needed to write modern day Java code. There is no excuse to write the Java code we used to write in imperative style like using loops and not using functional programming idioms. In fact, now it's one of the best practice in Java to favor functional programming and immutable data structure over imperative programming. More and more Technical Leads are enforcing developers to learn Java 8 and write better code leveraging improved API. The Java designers has done a fantastic job to convert any collection to Stream by adding stream() method into Collection interface. 

Difference between ByteBuffer vs byte array in Java

There are several differences between a byte array and ByteBuffer class in Java, but the most important of them is that bytes from byte array always reside in Java heap space, but bytes in a ByteBuffer may potentially reside outside of the Java heap in case of direct byte buffer and memory mapped files. Buffer is a byte array like abstraction which was introduced in Java NIO release to read and write data from FileChannel. It is extensively used in Java NIO for transferring data from one place to another and its also an essential Java concepts to know for any backend developer, particularly those who wants to create non-blocking server application using NIO in Java

Can you declare Abstract Class or Method Final in Java? If not, why?

If you are wondering whether you can use both abstract and final modifier together with a class or method in Java then you are not alone. This is one of the frequently asked, theory based Java questions which is sometime tricky to answer, particularly if you don't have complete knowledge of Java fundamentals. The answer of this question is No, you can not declare abstract class or method final in Java because both abstract and final keywords are mutual exclusive. Anything which is abstract cannot be final and vice-versa. It's like a person cannot be living and dead at the same time.

Top 10 Google Interview Questions for Software Engineer - Books, Resources

Hello guys, if you are preparing for Google's Software Development Engineer roles and looking or Google Software Interview questions then you have come to the right place. Earlier, I have shred Amazon and Microsoft Interview questions and in this article, I am going to share popular questions from Google Interviews. These Google interview questions are some of my favorites collected from different sources. Every Programmer knows that Google is one of the best technology companies and its dream for many software developers to work for Google, but at the same time interview process at Google is very tough and only a few genuine intelligent programmers get through their interview process

Difference between var, let, and const in JavaScript? Example Tutorial

Hello guys, there are many ways to declare variables in JavaScript like var, let, and const and many JavaScript developer get confused when to use which keyword for declaring a variable in JavaScript. If you also have same doubt and want to understand the difference between var, let, and const in JavaScript then you have come to the right place. This is one of the popular JavaScript interview questions and frequently asked during telephonic and face-to-face round of web developer interview. Knowing the difference will not only make you answer this question better during interview but also to write better JavaScript code in your day-to-day work. Earlier, I have shared the best books and JavaScript courses for beginners and in this article, I will tell you the difference between varlet, and const and when to use them. They are three different ways to declare variables in JavaScript. 

The 2023 Android Developer RoadMap

Hello guys, if you want to learn Android in 2023 or want to become an Android developer and looking for an Android Developer RoadMap then you have come to the right place. Earlier, I have shared best Android Courses and Books and in this article, I am going to share with you one of the most comprehensive Android Developer RoadMap you can find online. I love these Roadmap as they provide a comprehensive picture of what exactly you need to learn to become a professional Android developer and while they give more than what you need, its still better to have more than less as you can always learn remaining skills to become a better Android developer. 

Top 15 Advanced Java ClassLoader Interview Questions and Answers for Experienced Developers

Hello guys, if you are preparing for Java interviews and want to refresh your knowledge of Classloaders in Java then you have come to the right place. Earlier, I have shared Java interview questions on Collections, Multithreading, Serialization, and Generics, and in this article, I am going to share frequently asked Java interview questions about class loaders. If you don't know, a class loader is a program that loads classes in Java programs. The mechanism of class loading is very important to understand how the Java program works. When you run a Java program you give the name of the main class, from their onwards, built-in classloaders like Bootstrap classloader start loading not just the main classes but other Java library classes which is required to run that program. 

Top 20 Data Science Interview Questions and Answers

Hello guys, if you are preparing for Data Science interview or want to become a Data Scientist and looking for common Data Science questions then you have come to the right place. Earlier, I have shared Machine Learning Questions, Python Interview Questions, and AI Interview Questions and in this article, I am going to share common Data Science Interview Questions and answers for beginners and people with 1 to 2 years of experienced. There is a good chance that you are already familiar with these questions and can answer all of them if you have worked for a couple of years in Data Science field but if you struggle to answer any questions then you can always join these best Data Science courses to learn and revise those Data Science concepts. 

Top 15 Java NIO, Socket, and Networking Interview Questions Answers for Experienced Developers

Hello guys, if you are preparing for Java developer interview then you may know that Networking and Socket Programming is one of the important areas of Java programming language, especially for those programmers, who are working in client server-based applications. Knowledge of important protocols like TCP and UDP in detail is very important, especially if you are in the business of writing high-frequency trading applications, which communicate via FIX Protocol or native exchange protocol. In this article, we will some of the frequently asked questions on networking and socket programming, mostly based around TCP IP protocol. 

Top 20 Angular interview questions and Answers for 1 to 2 Years Experienced

Hello guys, if you are preparing for Angular developer interview or a web developer interview where Angular skills are required and looking for Angular interview questions to practice then you have come to the right place. Earlier, I have shared best Angular books and courses as well as web development interview questions and today, I am going to share Angular interview questions and answers for practicing interviews. Angular is one of the earliest frontend frameworks. The framework came out in 2010 at a time when modern development was starting to take place. It was, then, known as AngularJS. The popularity of AngularJS increased rapidly and it became one of the top frontend frameworks in no time. But soon, new landscapes were introduced in development, especially in JavaScript. AngularJS could not cope with it and the core team realized they needed to make the necessary changes. 

The 2023 Data Scientist and Data Engineering RoadMap

Hello guys, if you want to become a Data Scientist or Data Engineer in 2023 and looking for guidance like how to become a Data Scientist and Data Engineer in 2023 then you have come to the right place. In the past, I have shared best Data Science courses, tools, and best websites to learn Data Science and in this article, I am going to share the complete Data Scientist and Data Engineering RoadMap. This roadmap include all the skills, tools, and technologies you need to become a professional Data Scientist in 2023. While this roadmap is very comprehensive and contains tens of skills, tools, libraries, framework and programming language, they are divided into different categories like mandatory, good to know and other choices. 

Difference between IsNull and Coalesce in Microsoft SQL Server (with Examples)

Even though both ISNULL and COALESCE is used to provide default values for NULLs there are some key differences between them like ISNULL() is a T-SQL or Microsoft SQL Server-specific function or operator, and datatype and length of the result depends upon a parameter, but COALESCE is a SQL ANSI standard, it can accept more than one parameter and unlike ISNULL, the result doesn't directly depend upon a parameter, it is always the type and length of the value returned. Also, what is the difference between COALESCE and ISNULL is one of the frequently asked Microsoft SQL Server interview questions, and knowing these differences can help in both your day-to-day SQL development works and during job interviews.

The 2023 Golang Developer RoadMap

Hello guys, if you want to become a Golang Developer in 2023 or want to learn Golang in depth then you have come to the right place. Earlier, I have shared best online courses to learn Golang and Golang projects for beginners and in this article, I am going to share the complete Golang Developer RoadMap which you can follow to become a Golang Developer you always wanted to be. This is one of the most comprehensive Golang Developer RoadMap you can find on internet. It not only list all the mandatory tech skills you need to learn for Golang Backend development but also all the options and extra skills which can truly make you a competent Golang Developer in 2023. If you are wondering where to learn those skills then don't worry, I have also shared both free and best online resources to learn those skill in 2023. 

What is Generator Function in JavaScript? Example Tutorial

Hello guys, Functions are an essential part of JavaScript programming. Basically, a function is a piece of code that can take inputs and return outputs. Moreover, a function can be executed at any time and any number of times. When a regular function is called, it executes from top to bottom. Its execution ends when the function body ends or a return statement is encountered. But JavaScript provides a special kind of function that works in a different. These functions are called generator functions and they were introduced in ES6. In this article, we will discuss what are generator functions and how to use them with the help of an example. It's also a popular JavaScript interview questions, commonly asked to experienced developers.

What is state in React.js? useState Hook Example Tutorial

Hello guys, I have just started a new series, React for Java developers and I am going to publish React tutorials and examples to teach React.js, one of the most popular frontend libraries to Java developers. Since most full-stack Java development is happening on React and Spring Boot, it makes sense for Java developers to learn React.js. In the past, I have also shared both best React courses and books, as well as The React Developer RoadMap, which provides all the tools, libraries, and resources you need to become a proficient React Developer. 

React Project Example - How to create a React application using Redux hooks?

Redux is the most popular state management library. It is often used with React apps that are huge in size and state are shared among multiple components. Redux is a complex library to understand and even more complex to implement. It was even more complex and complicated before the introduction of react-redux hooks. Earlier, the connect method provided by Redux was used to connect React with the Redux store. Using connect method with other methods such as mapstatetoprops was complicated. But with the introduction of react-redux hooks, it is easy to use redux with redux. In this article, we will discuss what are react-redux hooks and how to use them with React.

The 2023 Blockchain Developer RoadMap

Hello guys, if you want to become a Blockchain Developer in 2023 and looking for guidance then you have come to the right place. Earlier, I have shared best Blockchain courses, books, and best websites to learn Blockchain technology and today, I am going to share how you can become a Blockchain Developer in 2023. Blockchain solutions are one of the most talked-about examples of technological innovation in recent times. Decentralization, transparency, and security in blockchain-based systems and applications can offer new routes for digital transformation. Amidst the growing hype around blockchain technologies, the role of a blockchain developer has become crucial for the emerging ecosystem.

Difference between SubStr vs SubString function in JavaScript - Tutorial Example

Hello guys, if you are wondering what is difference between SubStr() and SubString() function in JavaScript then you have come to the right place. JavaScript provides two similar-looking String manipulation functions, substr and substring, though both are used to get a substring from a String, there is a subtle difference between substring and substr method in JavaScript. If you look at their signature, both substr(to, length) and substring(to, from) both take two parameters, but substr takes the length of the substring to be returned, while substring takes end index (excluding) for substring. This main difference will be more clear when we will see a couple of examples of using substr and substring in JavaScript code.

Top 20 Web Development Interview Questions and Answers

Hello guys, if you are preparing for web developer job interview and looking for frequently asked web development interview questions then you have come to the right place.  Earlier, I have not just  shared HTML Interview QuestionCSS Interview Questions, and JavaScript Interview Questions, but also question from popular Frontend frameworks like React and Angular, and in this article, I am going to share common web development interview questions for 3 to 5 years experienced professionals. If you have worked as a web developer or created a couple of web projects then you may know answers of all of these questions but if you struggle to answer them then you can always go back and join any of these best web development courses to learn and revise key web development concepts. 

Top 25 Vue.js Interview Questions and Answers for Web Developers

Hello guys, if you are preparing for Vue.js interviews and looking for some frequently asked Vue.js questions from interviews then you have come to the correct place. Earlier, I have shared React.js Interview questions and JavaScript questions and in this article, I am going to share common Vue.js Interview questions for 1 to 2 years experienced web developers. With the success of libraries like React.js, developers around the globe are leaning more towards such flexible technologies. Though full-fledged frameworks like Angular are also popular and widely used, developers want flexibility.

Top 21 Maven Interview Questions with Answers for Java Programmers

Hello guys, if you are preparing for Java developer interviews then you should not ignore Maven as its on of the important build tool for Java developers. Most of the Java projects you are going to work will use Maven for building artifacts and deploying into both Physical machine and cloud. If you already know the importance of Maven and looking for frequently asked Maven interview questions then you have come to the right place. Earlier, I have shared 130+ core Java questions, Spring Boot questions, Hibernate Questions, and even JUnit questions for thorough preparation and in this article, I am going to share 20 common Maven questions from Java interviews with answers. 

Top 16 Lambda Expressions and Stream API Interview Questions Answers for Experienced Java Programmers

For a long time my readers were asking about some Java 8 interview questions, particularly on lambda expression, streams and around language changes e.g. default methods, method reference and functional interface. Finally, I am able to put some common Java 8 interview questions on lambda expression and Stream API and essential functional programming concepts like map, flatmap, and reduce together, which I going to share with you in this article, but before that, let's talk a little bit about impact of Java 8 in Java Developers interviews and why it's imperative for Java programmers to learn Java 8, particularly Lambda and Stream API

How to use hooks like useState, useEffect and useDispatch in React.js? Example Tutorial

Hello guys, if you want to learn about Hooks in React.js like useState, useSelector, useEffect, and useDispatch then you have come to the right place. In the past, I have shared the best React courseswebsites, and books and in this article, I am going to show you what is React hooks and how they make coding and statement management easier in React.js. If you remember, React.js is created by Facebook and ever since it came out in 2013 and since then, it has become one of the biggest players in the front-end development community. Today, React.js demand for frontend development is more than any other framework or library. There are several reasons for its popularity. React is flexible, easy to learn, programmer-friendly, and most importantly, it's high performing. 

10 Tools Cyber Security Professional and Pen Tester Should Learn in 2023

Hello guys, if you want to become a Pen Tester, Cyber Security Engineer or Ethical Hacker in 2023 and looking for the best tools then you have come to the right place. Earlier, I have shared best Cyber Security courses, free Pen Testing Courses, and Ethical Hacking courses and in this article, I am going to share best tools every Cyber Security Engineer and Pen Tester should learn in 2023 to do their job effectively. Suppose you become a penetration tester and learn the cyber security field. In that case, you need to know many tools that will help you scan the networks and system for vulnerabilities and other tools for exploring them. This article will provide you with the most used tools for finding these vulnerabilities and how to exploit them.

How to use useDispatch and useSelector? React Hooks Example Tutorial

Hello guys, if you are learning about React hooks and wondering how to use useDispatch and useSelector hooks in React application then you have come to the right place. Earlier,, I have shared the best React courseswebsites, and books and in this article, I am going to show you how React hooks make coding and statement management easier than it was before. The introduction of React hooks changed a lot in the react application development. Developers moved from complicated and length class-based components to simpler functional components that can do the same work in fewer lines of code. 

Top 20 Machine Learning Interview Questions and Answers

Hello guys, if you are preparing for Machine Learning Interviews and looking for common Machine Learning questions then you have come to the right place. Earlier, I have shared 35 Python Interview Questions and 20 AI Interview Questions and in this article, I am going to share 20 Machine Learning Interview Questions with answers. If you have gone through a Machine learning course or have worked in Machine Learning for a few months then you should know answer to all of these questions but if you struggle to answer them then I suggest you to revise concepts by going through these best Machine Learning courses for beginners. They are great to learn and revise important Machine Learning concepts. 

Top 20 Spring Data JPA Interview Questions Answers for Java Developers

Hello guys, if you are preparing for Spring and Java developer job interview and looking for common Spring Data JPA interview questions then you have come to the right place. Earlier, I have shared spring boot questions, spring cloud questions, spring security questions, and spring MVC questions and in this article, I am going to share 20 common Spring Data JPA questions with answers. These are simple questions focused on key Spring Data JPA concepts like finder methods, query methods, pros and cons of Spring Data JPA, how to implement Spring Data JPA repository interface etc. If you have done work or used Spring Data JPA in your project then most likely you will be familiar with those concepts but if not then don't worry, you can also checkout these Spring Data JPA courses to learn them in detail. 

Top 20 Spring Cloud Interview Questions and Answers for 3 to 5 Years Experienced

Hello guys, if you are preparing for Spring and Microservice developer job and need Spring cloud interview questions then you have come to the right place. Earlier, I have shared interview questions on Spring Boot, Spring MVC, Spring Security, Spring Testing and Spring Core and in this article I am going to share common Spring Cloud questions for Java and Microservice developers. If you have used Spring Cloud in your project then you can answer all of these questions easily but if you struggle to answer any of these questions then you can always go back and join one of these best Spring Cloud courses and best Microservice courses to learn and revise essential Spring Cloud concepts. 

Top 21 GraphQL Interview Questions and Answers for Beginners and Experienced Developers

Hello guys, if you are preparing for web developer interviews where GraphQL skills are needed and you are looking for frequently asked GraphQL Interview questions then you have come to the right place. Earlier, I have shared both Web development interview questions as well as REST Interview Questions and in this article, I am going to share 20 common GraphQL Questions from Interviews with answers. These questions covers essential GraphQL concepts like difference between REST And GraphQL and pros and cons of using GraphQL to consume APIs. If you have used GraphQL in past then you can easily answer these questions but if you forgot then you can always join of these best GraphQL online courses to learn and revise key GraphQL concepts.

Top 20 CSS Interview Questions and Answers for 1 to 2 Years Experienced Web Developers

Hello guys, if you are preparing for web developer job interview and looking for common CSS Interview Questions then you have come to the right place. Earlier, I have shared HTML Interview questions and CSS Interview Questions and in this article, I am going to share 20 common CSS Interview Questions with answers. If  you have used CSS for a couple of months then most likely you know the answer of these CSS questions but if you struggle with any of them then you can always go back to these best CSS online courses to revise key concepts. I have tried to include as many questions as possible covering different CSS concepts but you can also contribute, feel free to ask questions on comments. 

Top 35 Python Interview Questions with Answers 1 to 3 Years Experienced Programmers

Hello guys, if you are preparing for a Python developer job and looking for some frequently asked Python interview questions then you have come to the right place. Earlier, I have shared the Complete Python Developer RoadMap,  best books and best courses to learn Python and in this article, I am going to share 35 Python questions, covering different concepts for Python developer interviews. Sitting in any interviews, especially in tech interviews, is a tough job itself. You can't go in without proper preparation. Even if you have taken or given dozens of interviews, it is always recommended to go through the quick preparation notes or concepts.

Top 35 React.js Interview Questions Answers for Fullstack Java Developers

Hello guys, if you are preparing for React developer interviews and looking for frequently asked React.js interview questions then you have come to the right place. Earlier, I have shared the best courses, books, and websites to learn React.js and in this article, I am going to share 35 frequently asked React.js interview questions, suitable for 1 to 2 years experience developers. ReactJS is one of the most recently built open-source front-end programming languages. It came directly from Facebook's headquarter back in 2011. Earlier Recat.js was only limited to Facebook but now, it is one of the most extensively used programming languages all across the world.

Top 20 Apache Kafka Interview Questions Answers for Java Developers

Hello, guys if you are preparing for the  Java Developer or Apache Kafka interview and looking for frequently asked Apache Kafka interview questions and answers then you have come to the right place. Earlier, I have shared the best Kafka courses and popular interview questions on JavaJMSSpring Boot, and Hibernate and in this article, I Am going to share 20 frequently asked Apache Kafka interview questions with answers. Over the years, Kafka which is developed by Apache Software Foundation has gained popularity because of its immense capability of data processing. Apache Kafka provides a unified, high-throughput, low-latency platform for handling real-time data feeds and because of that it has become a go to choice for high-speed message for many fortune 500 companies.  

The 2023 Machine Learning Engineer RoadMap

Hello guys, if you want to become a Machine Learning Engineer in 2023 and looking for Machine Learning RoadMap then you have come to the right place. I love roadmaps and in the past, I have shared Java Developer RoadMap, Python Developer RoadMap, and Machine Learning courses and today, I am going to share with you The 2023 Machine Learning Engineer RoadMap. Machine learning is a good career nowadays since most companies implement them into their services to deliver a better user experience. Data scientists also use them to make predictions for better decision-making and other things. If you want to become a machine learning engineer and feel confused about starting, complete reading this article.

Top 15 TensorFlow Interview Questions and Answers for 1 to 2 Years Experienced

Hello guys, if you are preparing for Machine Learning Engineer interviews or a Data Science Interview and looking for popular TensorFlow interview Questions then you have come to the right place. Earlier, I have shared the best courses to learn TensorFlow and Machine Learning and in this article, we are going to share the frequently asked TensorFlow questions for Interviews. These questions cover key TensorFlow concepts and you can use them to revise TensorFlow before your interview. They are good for both screening and Telephonic rounds of interviews. 

Top 15 Node.js Interview Questions Answers for Fullstack Developers

Hello guys, if you are preparing for full stack web developer interviews then you should prepare for Node.js as well, particularly if you are a JavaScript developer. Node.js is one of the most popular terms in the web development community. It is heavily used in server-side development. It can be used with different databases such as MongoDB and SQL. There is a huge demand for Node.js developers in the job market. The interview can be tough because Node.js is wide and a person needs a considerable amount of practical experience to crack it. In the past, I have shared JavaScript interview questions, Angular interview questions as well as React Questions, and in this article, we will discuss the top 15 important and commonly asked Node.js questions with answers.

10 Reasons to Learn React Native for App Development in 2023

Hello guys, if you want to get into App development in 2023 then you have a couple of choices. For example, you can learn Flutter and React Native to develop cross platform apps, or you can learn Android or iOS to develop native apps. Android has been my favorite because you can use Java programming language to code Android application and being a Java developer, that was the easiest way to get into App development but if you are coming form JavaScript background then learning Java or Swift  (which is required for iOS app development) could be difficult. You can either learn Dart to use Flutter or you can stick with JavaScript and learn React Native, which I think the best way for a JavaScript developer to get into App development in 2023 but if you are still not convinced, In this article, I am going to share 10 reasons to learn React Native, which can help you make a decision on which technology you should learn for app development in 2023.

What is a Functional interface in Java 8? @FunctionalInterface Annotation Examples Tutorial

Hello Java programmers, if you are wondering what is a functional interface and what is the role of @Functional annotation in Java then you have come to the right place. Earlier, I have shared the best Lambda and Stream courses and books, and in this article, I will explain and teach you how to create a functional interface in Java. A functional interface is nothing but an interface with just one abstract method like Runnable, Callable, Supplier, Predicate, etc. You can use @Functional annotation to mark that this is a functional interface. If a function expects a functional interface then you can also pass a lambda expression to it and that's the main benefit of a Functional interface in Java. This is also a popular Lambda Expression Interview question so, knowing this topic in depth is also better for interviews. 

Top 30 Gradle Interview Questions with Answers for Java Developers

Hello guys, if you are preparing for Java developer interview then you must have come across Gradle, a Groovy based build tool which is gaining popular with Java community. While its not mandatory to learn Gradle for Java Interview if the job description mention Gradle or Groovy then you should prepare Gradle is one of the essential tool for Java developers. It's similar to  Maven and ANT, two other popular build tool for Java project but offers several advantages which I have explained in Maven vs Gradle post earlier.  These Gradle questions are good for both beginners and Java developer with 1 to 3 years of experience which are using Gradle in their project or expecting Gradle question on Java Interview.

Difference between char, varchar, nchar and nvarchar data types in SQL Server? Example

What is the difference between char and varchar in SQL, followed by nchar and nvarchar, is one of the popular SQL interview questions, and surprisingly not every programmer knows this basic difference. If you go with the name, which you should, then you can figure out that char is a fixed-length data type while varchar should be a variable-length data type. Though all char, varchar, nchar, and nvarchar are used to store text or String data there are subtle differences between them. As I said char is fixed length, which means a variable or a column like Zipcode char(10) will take only 10 bytes to store data, including space.

3 Best Spring Security Online Training Courses for Java Developers in 2023 [UPDATED]

Spring Security is one of the leading open-source, security frameworks that allow you to implement security in Java-based web applications. It provides several security features like authentication, authorization, the remember me functionality out-of-the-box, which means you can directly use them without adding code or changing your class. Yes, Spring Security implements security at the application level i.e. you can even secure your non-secure resource without modifying them. It is also the leading framework to secure RESTful Web Services. Because of all these, the demand for Java developers with good knowledge of Spring Security is very high.

Top 5 Online Courses to Learn C Programming in 2023 - Best of Lot

Hello guys, today, I will talk about one of the oldest, reliable, powerful programming languages that have survived for 50 years. Yes, that's right, 50 years. It's a great achievement for any technology to remain relevant for such a long period. If you don't know, the C Programming language is one of the first general-purpose programming languages, invented by Dennis Ritchie and Ken Thomson around 1969. Ken was writing UNIX, another accessible technology that has survived for 50 years around the same time and needed a programming language that can do all kinds of tasks; the result was a C programming language.

Top 5 Courses to Crack AWS Solutions Architect - Associate Exam (SAA-C03 and C02) in 2023 - Best of Lot

Hello guys, are you preparing for AWS Solutions Architect - Associate Exam?  or Do you want to become Amazon Web Services (AWS) Certified Developer to give your Cloud Computing career a push? and looking for some useful resources to prepare well for your exam then you have come to the right place. In the past, I have shared some free courses to learn AWS for beginner and in this article, I will share some of the best online courses to pass the AWS Solutions Architect - Associate Exam and become Amazon Web Services Certified Associate - a certification which will not only add value into your resume but also help you to get the high-paying job you always wanted.

3 Ways to Learn React.js for web development in 2023 - Best of Lot

Hello guys, if you want to learn React.js in 2023 and looking for best way to learn React.js in quick time then you have come to the right place. Earlier, I have shared React.js Developer RoadMap as well best React courses, books, websites, and React projects for you and in this article, I am going to share what is the best way to learn React.js in quick time and also in depth. But, before that, let's find out what is React.js and why every web developer should learn React.js in 2023. According to the Stack Overflow developer’s survey, React.js surpassed jQuery to become the most popular web framework in the world. Today, React is the most widely used technology for frontend development. Basically, React is a JavaScript library created and maintained by Facebook. It is used to create interactive and dynamic web components.

10 Reasons to Learn SQL for Programmers and Software Developers in 2023

Hello guys, if you are on the fence whether to learn SQL or not, or want to learn SQL but not sure whether learning SQL is worth your time and effort then you have come to the right place. Earlier, I have shared best SQL books and courses to learn SQL for Beginners and in this article, I am going to share 10 Reasons to learn SQL. From my 18 years of experience as Software developer and 12 years as a blogger I can safely say that you should learn SQL. In all of these times, I have constantly worked with SQL in my projects and job. While database changes form Oracle to MySQL, to SQL Server, and now PostgreSQL but the knowledge of SQL still pays off. 

5 Examples of GROUP BY Clause in SQL with Aggregate Functions

There is no doubt that SQL is an essential skill and every programmer, developer, DevOps, and Business analyst should know SQL. If you want to learn SQL from scratch then you have come to the right place. Earlier, I have shared many SQL interview questions and the best SQL courses for beginners, and today, I am going to share some GROPU By examples in SQL to write aggregation queries. THE GROUP BY clause in SQL is another important command to master for any programmer. We often use the GROUP BY command along with a select clause for reporting purposes, since the GROUP BY clause is mainly used to group related data together it's one of the most important SQL commands for reporting purposes. 

Top 20 PostgreSQL Interview Questions with Answers

Hello guys, if you are preparing for Postgres Interview or a Java development role where PostgreSQL skills are needed but not sure how to prepare, what to prepare etc and looking for PostgreSQL Interview questions with answers then you have come to the right place. Earlier, I have shared 50 SQL Phone interview questions and 6 SQL Query questions and in this article, I am going to share frequently asked PostgreSQL questions with answers. You can use these questions and answers to prepare well for your Job interview and you can also learn essential PostgreSQL concepts by going through these questions.

Strategy Design Pattern in Java using Enum - Tutorial Example

Hello guys, how are you doing? I hope you all are fine and doing good in your life and career. Today, I am going to talk about the Strategy pattern, one of the useful design and coding pattern which will help you to write flexible code. The code which can withstand the test of time in Production. I'll also teach you how you can use Enum to implement the Strategy design pattern and Open Closed design principle better in Java. I have said this before that Java Enum is very versatile and can do a lot more than you normally expect from it. We have seen a lot of examples of Enum in my earlier posts like writing thread-safe Singleton using Enum and 10 ways to use Enum in Java.

Top 30 Scala and Functional Programming Interview Questions and Answers

Hello guys, if you are preparing for Scala Developer interview and looking for frequently asked Scala questions for practice then you have come to the right place. Earlier, I have shared best Scala courses, Scala books, and best Scala Frameworks and in this article, I am going to share 30 Scala Questions from past interviews. Scala is a programming language which aims to provide best of both object-oriented programming and functional programming world. It not only allows you to  construct elegant class hierarchies for maximum code reuse and extensibility but also allows you to implement their behavior using higher-order functions and other functional programming technique. It is touted as one of the languages which can probably take over Java, though it didn't happen especially after Java 8 release which also provides some functional programming tools to Java e.g. lambda expression and stream

Top 20 Mockito Interview Questions with Answers for Java Programmers

Hello guys, if you are preparing for Java developer interview then you must prepare for Mockito, one of the most popular mocking and unit testing library for Java developers. Mockito is used across all kind of companies, both big and small like startups for unit testing Java applications and that's why good knowledge of Mockito is required to crack the Java Interview. Along with JUnit, Mockito is quite important and if you are looking for Mockito Interview questions and answers then you have come to the right place. Earlier, I have shared best JUnit and Mockito courses and unit testing books, and even popular JUnit interview questions and in this article, I am going to share 20 common Mockito questions for your interviews.

Top 10 Free Courses to Learn Docker in 2023 - Best of Lot [UPDATED]

I have been answering a lot of questions about what programmers should learn in 2023, and Docker Container is one such skill. Docker and containers are a whole new way of developing and delivering applications and IT infrastructure. In this post, I'll talk about what Docker is and why a programmer should learn Docker. In today's world of massive scalability, where every single mobile app and web application needs to support billions of users (think of YouTube, WhatsApp, Uber), software application development and deployment have become increasingly complex. Gone are the days when the software is developed by a small team of onshore people.

Top 10 Data Science Certification Courses for Python and R Developers in 2023 - Best of Lot

Hello guys, Data Science, Machine Learning, Deep Learning, and Artificial intelligence are really hot at this moment and offering a lucrative career to programmers with high pay and exciting work. It's an excellent opportunity for programmers who are willing to learn these new skills and upgrade themselves. It's also important from the job perspective because Robots and chatbots are getting smarter day by day, thanks to these technologies, and most likely will take over some of the jobs which many programmers do today. Hence, it's essential for software engineers and developers to upgrade themselves with these skills.

Top 17 Debugging Interview Questions for Experienced Java Programmers

Hello guys, if you are a beginner or an experienced Java developer with 1 to 3 years of experience under your belt, when you go for a Java interview you should prepare some Java debugging interview questions like how to debug a Java program running in Linux environment etc. In the past, I have shared 130+ core Java questions, 50+ Multithreading Questions, 25+ Java Collection questions and 50+ Lambda and Stream interview questions and in this article, I am going to share 17 questions to test debugging skills of Java programmers. These are the questions which I have seen during my own interview as candidate and also asked as Interviewer and there is chance that you may have also seen it on your interview.

Top 35 T-SQL and Microsoft SQL Server Interview Questions and Answers for 2 to 5 Years Experienced

Hello guys, if you are preparing for Java developer interview where Microsoft SQL Server is listed as mandatory and required skill or you preparing for a junior DBA role for Microsoft SQL Server and looking for common SQL Server interview questions for practice then you have come to the right place. Earlier, I have not only shared SQL Server courses for beginners but also 50+ SQL and Database Questions for programmers and DBA. You an also check them to get yourself familiar with generic SQL concepts like normalization, joins, aggregation, partitioning, indexing, and transaction along with these SQL Server specific questions which focuses mainly on T-SQL and SQL Server functionalities and how general SQL commands behave in Microsoft SQL Server. 

12 Examples of Kubectl command in Kubernetes in Windows and Linux

Hello guys, if you are working with Kubernetes pods like deploying your application, starting and stopping them by scaling to zero instances, while you just want to see logs or want to login into the Kubernetes pods itself, you must know how to use kubectl commands to do all these task. Since most of the companies, both big and small are using Kubernetes to deploy services on cloud, its imperative for Java developers and other Software developers to get familiar with the kubectl command. We deploy our Java Microservices on Kubernetes mainly because Kubernetes can start the services automatically when it goes down. We have different Kubernetes clusters for different environments like DEV, UAT, and PRODUCTION and I often switch between those cluster using kubectl commands to check the status of our Java services or interact with them.

Top 42 Programming Interview Questions with Answers for 1 to 3 Years Experienced

For the last few years, phone interviews also known as the telephonic round is the single most popular way to screen candidates in a programming job interview. It's easy for both parties to gauge each other, the candidate doesn't need to travel to the prospective Employer's premises and the Interviewer also doesn't need to make any necessary arrangements. This is the second part of my article on programming interview questions, in the first part, I got feedback that it is a little bit heavy on coding-based questions and many programmers asked me to share a similar list for the telephonic round of programming Interviews. In order to clear the telephonic round and proceed to the next round, you must be good enough to answer all the questions related to your Job description.

Template Method Design Pattern in Java? Example Tutorial

Template Method Pattern defines a sequence of steps of an algorithm but let you free to implement those steps on your way. You cannot change the algorithm but you can define how those steps should behave. To make sure that you cannot change the algorithm, template methods are usually made final in Java, which is also a good use case of when to make a method final in Java. The subclasses are still  allowed to override the steps but as I said, they are not allowed to change the sequence. It can also be provided a default implementation for one or more steps. Let us look at the following example to understand Template Method Pattern.  A Template method pattern provides a skeleton for performing any sort of algorithm or an operation, and it allows the sub-classes to re-define part of the logic

How to check if a String has all unique characters in Java? [Solved]

Hello guys, its been long time since I shared any interesting coding problem but the wait is over. Today, I am going to share one interesting and popular String based coding problem which you would love to solve. Today's coding challenge is to find out if a given string has all unique characters or not, for example, if given String is "Java" then your function should return false because all styles from this String are not unique. On the other hand, if the given String is "Python," then your function should return true because all characters are unique in this String. Btw, don't just jump on the solution if this is ever asked to you on Interview; instead, you should ask a couple of good questions to demonstrate your requirement gathering skill and attention for details.

How to enable disable Form elements using jQuery? Example Tutorial

In last couple of tutorials you have learned how to get all selected checkbox and radio buttons, and in this tutorial, you will learn how to enable/disable form elements using jQuery. A form element e.g. a text field, radio buttons and checkbox, all represented using input tag can be enabled or disabled by adding an attribute called "disabled". It's similar to "checked" attribute we have seen for checkbox and radio buttons. If this attribute is not present then element is enable, but if this attribute is present then you can use disabled=true to disable the form element and disabled=false to enable the form elements as shown in our example.  Like previous example of checking/unchecking checkbox, you can use prop() jQuery function to enable/disable form element if you are running on jQuery 1.6 or higher version and attr() function if you are running on jQuery 1.5 or lower version. 

Top 10 Free Courses to Learn Python in 2023 - Best of Lot

There is no doubt that Python is currently the world's #1 programming language and the biggest advantage of that is it's bringing more and more people into the programming world. In recent years, I have seen more people learning Python than any other language, yes, not even JavaScript. Many of them learning Python to explore some awesome Data Science and Machine learning libraries provided by Python. Some people are also learning Python for web development and there are still many developers who are learning Python for scripting and automating trivial tasks. It doesn't matter why you are learning Python at this moment, it's a great thing in itself that you have decided to learn Python.

5 Examples of df command in Linux

The df command is used to find the amount of disk space used and available on different partitions and file systems. The simplest example of df command is just typing df on console with out any arguments and it will show you the space used and available on all currently mounted file systems of all types e.g NFS, ext3 and both local and remote. Alternatively you can ask df command to print the size and space available and used for a particular partition. Normally the disk space is printed in units of 1024 bytes, but this can be overridden. I commonly use df -h option to print the size and disk usage in human readable format e.g. G for giga bytes, M for mega bytes and so on. 

Top 10 Angular Tutorials and Courses for Web Developers in 2023 - Best of Lot

Hello guys, if you are interested in learning the Angular framework in 2023, one of the best and most popular JavaScript frameworks for developing component-based Web GUI, and looking for some awesome courses, books, and tutorials then you have come to the right place. Earlier, I have shared the best Angular courses and In this article, I am going to share some of the best resources like books, tutorials, and courses to learn the Angular framework, formerly known as Angular, and now famous as Angular 2. It's backed by Google; hence you should not worry about it being outdated and losing relevance in a couple of years. Any investment you made in learning Angular will pay you rich dividends in the coming years.

Top 5 React and Redux Courses to Learn Online in 2023 - Best of Lot

If you are a Web developer or someone passionate about web development and looking for some awesome courses to learn React or React JS, a popular JavaScript framework to develop a component-based user interface then you have come to the right place. Facebook's React library has taken the front-end development world by storm. More and more people have started using React even in favor of Google's Angular, another popular front-end development framework. Well, I am not going into the classic debate of Angular vs React as both the framework has their own advantage and disadvantage but if you have chosen to learn React, you have made the right decision.

3 ways to parse JSON String to Object in Java [Jackson, Gson, and json-simple Example]

One of the common task in Java web application, particularly the ones which deals with RESTful web services are parsing JSON messages. Many times you need to parse JSON to create a Java object like parsing a JSON message to create a POJO,  for example, an Order or a Book. Representing JSON in Java is easy, it's like a String value but unfortunately, JDK doesn't provide any standard API to parse JSON in Java. There were talks to add JSON parsing API in JDK 9 but that didn't materialize, but you don't need to worry. There are many good open-source JSON parsing libraries you can use to parse any kind of JSON in your Java program. 

How Long Does It Take To Learn Cyber Security?

Hello guys, if you want to become a Cyber Security Engineer or a Cyber Security Analyst and wondering how long it take to learn all essential Cyber Security concepts then you have come to the right place. Earlier, I have shared best Cyber Security online courses, Pen testing certification courses,  and Ethical Hacking online courses to become a Security specialist in 2023 and in this article, I am going to share how you can learn Cyber Security and how much time it take to learn Cyber Security concepts, tools, and practices. Cyber security is a massive industry that involves protecting data from unauthorized access either locally on your devices such as a laptop, computer, phone, router, local network, or the data on the server that holds the companies data such as users information and their credit card. This article will help you estimate the time needed for learning cyber security and which skills are essential.

Top 5 SQL Server Management Studio Tips for Programmers and DBAs

Hello guys, If you use SQL Server database and use SQL Server Management Studio in your day to day work and looking for tips to improve productivity and work fast and efficiently then you have come to the right place. Earlier, I have shared SQL Server online courses, SQL Server Interview questions and SQL Server Management Studio keyboard shortcuts and today, I am going to share amazing tips to make most of SSMS. These are the tips I learned hard way after working close to 8 years on SQL Server backend. Anyway, we all love tips? isn't it? Well, I certainly do, they not only make life easier on work but also gives us a joy of discovery. Every time I discover a not-so-trivial tip I feel happy and become more productive and that's why I am always in hunt of useful tips which can help me in my work. 

Area and Perimeter of Square in Java Program? Example Tutorial

Hello guys, if you are looking for Java program to calculate area of Square or program to calculate perimeter of square or just learning Java and looking for programming exercises then you have come to the right place. I have share many programming exercises and homework in this blog and today, I am going to share another simple programming assignment for beginners. Yes, we ae going to write a program which will calculate the area and perimeter of a square in Java. If you don't remember, area of a square is nothing but the multiplication of side with itself or square of side, while perimeter of a square is 4 times of its side because in case of square, each side is equal. 

Why use Date as YYYYMMDD in SQL Server?

When you enter a Date in SQL SERVER for inserting data or filtering data in WHERE clause, what you enter is String. SQL Server infernally converts that formatted String to different date and time data types in Java e.g. DATETIME, DATE, TIME, DATETIME2 and SMALLDATETIME. This conversion is subject to language setting in SQL SERVER, for example, the same date 03/07/2015 can be interpreted as 3rd March 2015 if language setting is US English (MMDDYYYY) and 3rd July 2015 if language is set to British English(DDMMYYYY). To avoid this, you can enter date as YYYYMMDD format, which is considered language neutral and always interpreted correctly by Microsoft SQL Server.

Top 5 Frameworks for Microservices and Cloud Native Development in Java in 2023 - Best of Lot

Hello Java Programmers, if you are thinking about Microservice and Cloud-Native development in Java and exploring options like frameworks, libraries, and technologies then you have come to the right place. Earlier, I have shared the best Microservice courses, and Microservice design patterns and in this article,  I am going to share the best Microservice Framework for Java developers. While you may know that Spring Boot and Spring Cloud is the leading framework for developing Microservice applications in Java, there are a couple of more options as well like MicroNaut, DropWizard, and Quarkus IO. In this article, you will learn about the top 5 frameworks you can use to develop Microservice in Java.

How Long Does it Take to Learn Machine Learning in 2023?

Hello guys, if you want to learn Machine Learning in 2023 and wondering how long does it take to learn Machine Learning and become a Machine Learning Engineer then you have come to the right place. Earlier, I have shared best free Machine Learning courses and books and in this article, I will share how much time it take to learn Machine Learning and how you can quickly learn essential ML concepts and become a Machine Learning Engineer in 2023 but before that let's see what does Machine Learning means? Machine learning is the science of making the machine predict the result of something based on previous data. 

Top 10 Frameworks to become a Full Stack Developer in 2023 - Best of Lot

The Technical world changes as fast the technology changes, and so are the technical jobs. Gone are the days where you can land a job by just knowing one technology or programming language, and somehow survive in the position for many years without learning new things. Many of us get into the programming and web development world by knowing just one or two technology like Java, C++, or JavaScript, but that won't cut the ice anymore. There were teams of tens of people doing specialized jobs like front-end development is done by a separate set of developers and back-end is written by other sets of programmers, commonly known as server-side developers.

Top 5 Online Courses to Learn Flutter in 2023 - Best of Lot

If you are like me, who thinks Flutter is the future of mobile development and looking for some excellent online courses to learn Flutter, then you have come to the right place. In this article, I am going to share some of the best online courses to learn Flutter in 2023 from Udemy, Pluralsight, and Coursera, but before going into that, let's see what Flutter is and why everyone is so excited about it. Well, in general, whenever something comes from Google, it makes a lot of developers excited like Angular, Dart, and now Flutter. I have got my hand dirty in both Android and iOS using Java and Objective-C in the past, but after working for some time, I decided to move on.

10 Reasons to learn MongoDB NoSQL Database in 2023

Hello guys, If you are in web development or Software development then you may know that databases are an important part of modern development. Be it web or mobile application development, you will always find some kind of database in it. Modern development is not complete without databases because data is required to be stored somewhere. As a Java developer I have worked across many projects and most of them have relational database but things are changing nowadays and more and more project are using NoSQL Databases like MongoDB, Redis, Cassandra etc which can really improve performance in many specialized cases. 

10 Tools Java Developers Can Learn in 2023 - Beginner to Advanced [UPDATED]

Hello guys, we are now one week into 2023, and I am sure all of you have already made your goals about what to learn in 2023 and how to achieve them. I have been writing a series of articles to give you some ideas about the things you can learn and improve to become a better, all-around developer in 2023, like learning new programming languages, frameworks, and libraries. These three things are extremely important and help you to become a better Java developer but as some wise person said, "you are only as good as your tools", you should also look to upgrade your tools, learn new tools and improve your understanding of old tolls which are still going well.

How to remove objects from ArrayList using Iterator in Java? Example Tutorial

It's tricky to remove objects from ArrayList in Java while you are not iterating over it, especially if you are new to Java programming.  Altought, you can use any of the overloaded remove(object obc) and remove (int index) method to remove objects directly or at any index. But, things get tricky, when you are iterating over ArrayList. If you use the remove() method from ArrayList then it will throw ConcurrentModficationException, even if you are running your code from single thread. The reason is that, Iterator checks for any modification during iteration using modCount and if it sees a modification e.g. add or remove which happens outside Iterator, it throws ConcurrentMdoficationException. Hence, the right way to remove objects from ArrayList is to use the Iterator's remove method, instead of remove() methods from ArrayList. It will help you to avoid ConcurrentModficiationException

Database Per Microservice Pattern in Java - Example Tutorial

Hello guys, in the last article, I share with your 10 essential Microservice design patterns and principles and best Microservices courses for Java developers which many of you appreciated. At the same time, a lot of you asked me to go deep down into each of those patterns and explain them with examples. So I decided to create this new series of Microservice Pattern tutorials where I will explain each of those essential Microservice pattern with example every week. In this article, let's have a look at what is database per microservice. Microservice architecture is a combination of a set of loosely coupled microservices and each service can be developed independently in an agile manner. We can use this pattern and practices when designing microservices. So let's go deep into what is database per microservice is and why we use it in our programming. 

12 Best Coursera Professional Certificates for IT Professionals in 2023 [UPDATED]

Hello guys, If you are thinking of a career in Information Technology and Software Development in 2023 but lack a Computer Science degree or a Professional degree then you don't need to disappoint. Coursera's professional certificates can give you all the knowledge and credential to start a career in Information Technology. If you don't know, Coursera launched Professional Certificates recently which can help you get job-ready for an in-demand career field in less than a year. You can earn a career credential, apply your knowledge to hands-on projects that showcase your skills for employers and get access to career support resources.

[Solved] How to check if given point is inside Triangle or not in Java? Example

One of the interesting problem from Java Programming interviews is, "write a program to check if given point lies inside a triangle or not?". You will be given co-ordinates of vertices and the point as part of problem and you need to write a function e.g. isInside() which return true if point is within the triangle and false if it is not. For example, in the triangle specified by vertices (11, 31), (21, 1), and (1, 1) the point (11, 16) are inside the triangle and point (30,17) are outside of the triangle. It's a good coding interview question if you have not heard before, just think about how do you prove if the point lies inside the triangle or not? It's not a difficult algorithm and you can think of it by just trial and error. 

10 Tips to Become a Better Java Developer in 2023 [UPDATED]

I often receive emails from my readers about how they can become better Java developers, what things they should learn, and which areas they can work on to become a Rockstar Java developer. After answering them individually over the last few years, I thought to jot down a couple of points, which I think will make you a better Java Programmer and Application developer. But, before going into that, I would like to stress that a better programmer is always a better Java developer, and that's why all the tips I have shared before to improve your programming skill and become a better programmer still hold true. If you haven't read them yet, you can understand them after this article; they will help you to improve your programming and coding skills, which is essential to becoming a better Java developer.