Data Engineering & AI Interview Playbook

[ Updated for 2026] : [This article was originally written in 2022 and has been revised to reflect current Data Engineering and AI interview trends.] In recent years, the exponential growth of data—driven by cloud adoption, digital products, IoT, and AI systems has made data a core business asset for almost every organization. As a result, companies across industries are heavily investing in data platforms to enable analytics, real-time insights, and AI-driven decision-making. This shift has significantly increased demand for Data Engineering roles, and Data Engineers continue to be among the most in-demand and strategically critical profiles in the IT industry. By 2026, the role of a Data Engineer has evolved beyond traditional ETL development. Organizations now expect Data Engineers to design scalable, reliable, and AI-ready data platforms that can support analytics, machine learning, and Generative AI use cases. Modern data teams rely on Data Engineers to build robust ingestion p...

The name NoSQL itself tells us that it is "non-SQL" or "non-relational" database. Around 30 years back when the data used to be non-changing and smaller in size, traditional relational databases were more prominent like ORACLE, Postgres and so on which had fixed schemas. But during the last decade, the data has grown exponentially and it is also changing quickly. The traditional databases have failed to handle this BIG DATA effectively. So there was a need to introduce the database that can adapt itself with ever-changing data and that can handle the enormous size of data. And thus NoSQL databases came into the picture. Nowadays NoSQL databases have been referred to as "Not Only SQL" databases which means that these databases may support SQL like query languages and can be a part of polygot persistent architecture along with other relational databases. The data structures used in the NoSQL database are more efficient than the data structures used by ...

In the last post What is Apache Kafka , we discuss Kafka producer, Topics and Consumers. In this post, I am going to provide JAVA code for writing Kafka Producer and explain how it works. In this code, we are going to send data from CSV row by row to Kafka Topics for further consumption by Kafka Consumer . In this way, we can generate the continuous streams of Data. 1. First, you need to create a Kafka Topic. You can either do it from the console or do programmatically. Please go through the basic Quickstart from  Apache Kafka Website  and create Topics, send basic message from producer and consume it at consumer. Once, you have created Topic, its time to write Kafka Producer, which will send data to Topic. For creating Procuder we need to configure it some parameters. Lets, look at the configurations required for creating producer 1. List of Kafka Brokers 2. Serializer used for sending data to Kafka 3. Acknowledge from Kafka that messages are properly r...

Kafka is a fast, scalable, durable, and fault-tolerant publish-subscribe messaging system that sends messages between applications, processes, and servers. It is composed of three important components called producer (which acts as Sender), Topics (topic or category of messages), and Consumer (which acts as a Reciever) . Kafka aims to provide high-throughput, low latency for real-time data feeds. It is widely used for real-time streams analytics, ingestion data into Spark, Complex Event Processing, Log aggregation, etc. Before understanding Kafka Architecture, lets first understand what Kafka Broker is Kafka Broker: As Kafka is a distributed framework, Kafka's cluster consists of different servers called Brokers running Kafka. Producers publish the message to Kafka Topics within this Broker and consumer consumes this message from Topics. Kafka Architecture: Kafka Architecture is comprised of mainly 3 components Kafka Producer Kafka Topics Kafka Consumer ...

In this post, I am going to discuss the top 5 JAVA interview technical questions that are frequently asked in the technical interview of big IT companies that are looking for JAVA developers. 1.  What is Method Overriding in JAVA? One of the most common technical interview questions 1. Method overriding is used to enable sub-class to use same Method name, same number, and type of arguments and same return type of super-class 2. It is run-time polymorphism 3. The methods must have the same signature. Example: class Book { void run(){ System.out.println(“Book is issued”); } Class MathBook extends Book{ void run() { System.out.prinltn(“MathBook is issued to Maths Student”); } public static void main( String args[]) { Book b=new MathBook(); b.run(); } } 2. What are Threads in JAVA? How to create Threads? Again very important IT interview question A thread is an independent and isolated path of execution in a single program. Many thr...

Python is the most widely used programming language nowadays and it is one of the favorite languages among developers. Also, with the latest growth in Big data, Data Science, and Machine Learning, python is most popular in the Big Data community. So, companies working with Big Data expect knowledge of python, and concepts of python are frequently asked in interviews.  In this post, I will share the technical questions interview experience and  top 5 basic python technical questions which are frequently asked in many technical interview. 1. Describe Memory Management in Python It is one of the most common IT interview questions. Memory management in Python involves a private heap containing objects and data structures. The management of this private heap is handled by the Python memory manager. Python memory management also deals with various dynamic storage aspects like sharing, segmentation, and pre-allocation. The programmer doesn't have access to private heap sto...

Recently, you might have come across a word Kotlin, so in this post, I am going to share about Kotlin and how it is different from JAVA? What is Kotlin? Kotlin is statically typed programming language developed by JetBrains that runs on Java Virtual Machine. It can also be compiled to JavaScript source code. Kotlin is expressive, concise and powerful as it combines object-oriented Programming and functional programming features. It is focused on interoperability, safety and tooling support. Lately, it is really popular within the Android community and most of the developers are switching towards Kotlin. The reason being that Kotlin reduces the lines of code and make it more convenient process for the developers. Let's look at the few important differences between Kotlin and Java Kotlin vs Java : Function Types: Kotlin has the ability to pass the function as a parameter to other functions without resorting to single abstract methods like callable, runnable etc, ...