There are two types of data storage databases one is a row-oriented database and another one is a column-oriented database.

Row-Oriented (ACID Transactions): They are databases that organize data by the record, keeping all of the data associated with a record next to each other in memory. Row-oriented databases are the traditional way of organizing data and still provide some key benefits for storing data quickly. They are optimized for reading and writing rows efficiently.

Common row-oriented databases:

Column-Oriented (Analytics): They are databases that organize data by field, keeping all of the data associated with a field next…


Hello there, today I want to introduce Docker Volume to you if you are recently using Docker and feeling very painful while synchronizing your local code inside the Docker container.

Maybe you have already heard that we can use volumes to maintain and persist state for the containers in production. But do you know that volumes can also be an excellent tool for speeding up your development workflow?

What is a Volume?

Docker’s official documentation: Volumes are the preferred mechanism for persisting data generated by and used by Docker containers. …


Hello, I would like to guide you how to launch a local Kubernetes cluster (minikube), develop an app using the Spring Boot framework and deploy it as a container in Kubernetes.

The app can let you do so:

Get started with the initialisation of Spring Boot

You will build a simple web application with Spring Boot and add some useful services to it.

First we need to create a Spring Boot application, which can be done in a number of ways.

Using the Initialiser Website

  1. Visit https://start.spring.io and choose the Java language and Maven project.


Data classes in python allow you to write shorter code and initialize print compare and audio data much more easily. Let’s take a look !

First of all, classes are a combination of two things: Behaviour in the form of methods and data in the form of class attributes. Their blueprint for objects, they form the basis of object-oriented programming and developers use them in a million different ways. Some classes are mostly containers of behaviours, for example a class that allows you to draw all kinds of shapes on the screen or a class that provides password hashing functionality…


Hi there !

Today I’m going to talk about one of questions that are important but easily ignore by us : equals() and hashCode() methods in Java.

I found both these methods extremely important in the development process, so if the person knows nothing about them, it can cause a lot of the issues in the application like missing data inside the hashed data structures, wrong equality process results, etc.

So, come with me and let’s move on to discover these 2 methods.

As you might know, there is a class Object, that is a parent of each other class…


Hi there !

I’m recently reading some books and preparing for the OCA certification assessment and I want to share some interesting parts that are always omitted by us.

In Java, there are two types of exceptions:

Checked Exception

They are the exceptions that are checked at compile time. If some code within a method throws a checked exception, then the method must either handle the exception or it must specify the exception using throws keyword.

Invalid external conditions that cannot be directly controlled by the program.


Bubble Sort is the simplest sorting algorithm that works by repeatedly swapping the adjacent elements if they are in wrong order. The pass through the list is repeated until the list is sorted. The algorithm, which is a comparison sort.

Bubble sort has a worst-case and average complexity of O(n²), where n is the number pf items being sorted.

How Bubble Sort Works ?

  1. Starting from the first index, compare the first and the second elements. If the first element is greater than the second, they are swapped. …


A Java operator is a symbol that can be applied to a set of variables, values, or literals — referred to as operands — and that returns a result. Three types of operators are available in Java: unary, binary, and ternary. These types of operators can be applied to one, two or three operands, respectively. You’ll need to know a specific subset of Java operators, how to apply them, and the order in which they should be applied.

Java operators are not necessarily evaluated from left-to-right order. …


What are Arrays in Java ?

“An array is a container object that holds a fixed number of values of a single type. The length of an array is established when the array is created. After creation, its length is fixed.”

The above paragraph is from Oracle Java Official Document, we can know that an array has features such as:

That is, generally, an array can help us to store several elements with same type (like a bank but only provide service to one specific currency), however, we are not allowed to add one more element to the array if…

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