200+ Synechron Interview Questions and Answers

SQL is a programming language used to manage and manipulate relational databases.

• SQL stands for Structured Query Language

• Queries are written to retrieve, insert, update or delete data from a database

• Basic syntax: SELECT column1, column2 FROM table_name WHERE condition

• Example: SELECT * FROM customers WHERE city='New York'

• Other commands include INSERT, UPDATE, DELETE, CREATE, DROP, etc.

Hashmap and hashset are data structures used to store and retrieve data efficiently.

• Hashmap uses key-value pairs to store data and allows null values for both keys and values.

• Hashset stores unique values and does not allow duplicates.

• Both use hashing to locate and retrieve data quickly.

• Hashmap is implemented using a hash table while hashset is implemented using a hash map.

Using Streams API to find occurrence of each element in an array of strings

• Use Arrays.stream() to convert the array to a stream

• Use Collectors.groupingBy() to group elements by their occurrences

• Use Collectors.counting() to count the occurrences of each element

Batchcom is a utility used for batch communication between two systems.

• Batchcom is used to transfer data between two systems in a batch mode.

• It is commonly used in mainframe environments.

• Batchcom can be used to transfer large amounts of data efficiently.

• It can also be used to automate batch processes.

• Batchcom supports various file formats such as fixed-length, variable-length, and delimited files.

Indexes are data structures that improve the speed of data retrieval operations in a database.

• Indexes are used to quickly locate data without having to search every row in a database table.

• Types of indexes include clustered, non-clustered, unique, and composite indexes.

• Clustered indexes determine the physical order of data in a table, while non-clustered indexes store a separate copy of the indexed columns.

• Unique indexes ensure that no two rows have the same values in the ind...read more

Use a sorting algorithm like bubble sort or quicksort to sort the array without using built-in methods.

• Implement bubble sort algorithm to compare and swap elements in the array.

• Alternatively, implement quicksort algorithm to recursively divide and conquer the array.

• Ensure to handle edge cases like empty array or array with only one element.

Node.js Event Loop is a mechanism that allows Node.js to perform non-blocking I/O operations.

• The Event Loop is responsible for handling asynchronous operations in Node.js.

• It allows Node.js to perform I/O operations without blocking the execution of other code.

• Event Loop continuously checks the event queue for new events and executes them in a loop.

• Node.js uses libuv library to implement the Event Loop.

Automate sauce demo login functionality using code

• Use Selenium WebDriver to automate the login process

• Identify the username and password fields using locators

• Enter valid credentials and click on the login button

• Verify successful login by checking for the presence of a welcome message

Automate getting product prices by their names

• Create a function that takes in an array of product names as input

• Use a web scraping tool like Selenium to extract prices from a website

• Map the product names to their corresponding prices and return the result

Background keyword is used to define steps that are common to all scenarios in a feature file.

• Background keyword is used to reduce code duplication in feature files.

• It is defined at the beginning of a feature file, before any scenarios.

• Steps defined in the background section are executed before each scenario in the feature file.

• It is useful for setting up preconditions or initializing data that is required for all scenarios.

• Example: Given a user is logged in, When they naviga...read more

Data structures are used to organize and store data in a way that enables efficient access and modification.

• Data structures can be classified as linear or non-linear

• Examples of linear data structures include arrays, linked lists, and stacks

• Examples of non-linear data structures include trees and graphs

• Data structures can be implemented using various programming languages

• Efficient algorithms for searching, sorting, and manipulating data depend on the choice of data structure

Java program to count characters in a string

• Use a HashMap to store character counts

• Iterate through the string and update the counts in the map

• Handle both uppercase and lowercase characters separately

CI/CD pipeline is a set of automated processes that allow developers to deliver code changes more frequently and reliably.

• CI/CD stands for Continuous Integration/Continuous Delivery.

• CI involves automatically building and testing code changes frequently to catch errors early.

• CD involves automatically deploying code changes to production after passing tests.

• CI/CD pipelines typically include stages like build, test, deploy, and monitor.

• Popular CI/CD tools include Jenkins, GitLab...read more

Write-behind and write-through are caching schemes used to improve performance and data consistency.

• Write-behind cache scheme delays the write operation to the main storage until it is necessary, improving write performance.

• Write-through cache scheme writes data to both the cache and the main storage simultaneously, ensuring data consistency.

• Write-behind is suitable for scenarios where write performance is critical, but data consistency can be compromised temporarily.

• Write-th...read more

OOP in Python involves creating classes and objects, encapsulation, inheritance, and polymorphism.

• Classes are used to define objects and their properties

• Encapsulation ensures that data is hidden and can only be accessed through methods

• Inheritance allows for the creation of subclasses that inherit properties and methods from a parent class

• Polymorphism allows for the use of a single method or function to handle different types of objects

• Python supports multiple inheritance and ...read more

MVVM is a design pattern that separates the UI from the business logic by introducing a middle layer called ViewModel.

• Model-View-ViewModel design pattern

• ViewModel acts as a link between the Model and View

• Data binding is used to connect the ViewModel to the View

• Updates in the ViewModel automatically reflect in the View

JWT authentication in Web API involves generating a token with user credentials and validating it on subsequent requests.

• JWT stands for JSON Web Token, which is a compact and self-contained way for securely transmitting information between parties as a JSON object.

• In Web API, a JWT token is generated upon successful authentication and is sent to the client.

• The client includes the JWT token in the Authorization header of subsequent requests to access protected resources.

• The We...read more

Indexes are data structures that improve the speed of data retrieval operations in a database. There are different types of indexes.

• Indexes are used to quickly locate data without having to search every row in a database table.

• Types of indexes include clustered indexes, non-clustered indexes, unique indexes, and composite indexes.

• Clustered indexes physically reorder the data in the table based on the index key.

• Non-clustered indexes store a separate copy of the indexed columns...read more

A webform is an online form used to collect information from users on a website.

• Webforms typically include fields for users to input their name, email, and other relevant information.

• Webforms can be used for various purposes such as contact forms, registration forms, surveys, and more.

• Webforms can be created using HTML, CSS, and JavaScript, or through online form builders like Google Forms or Typeform.

Use hashing to find files with duplicate content efficiently.

• Create a hash function to generate a unique identifier for each file's content.

• Store the hash values in a dictionary with the corresponding file paths.

• Identify files with duplicate content by checking for duplicate hash values.

• Return a list of file paths with duplicate content.

DMS and SMS are concepts related to testing. DMS stands for Defect Management System and SMS stands for Test Management System.

• DMS is used to track and manage defects found during testing.

• SMS is used to manage the entire testing process, including test planning, execution, and reporting.

• DMS and SMS are often integrated to provide a comprehensive testing solution.

• Examples of DMS include JIRA, Bugzilla, and HP Quality Center.

• Examples of SMS include HP ALM, IBM Rational Quality ...read more

During my leisure time, I enjoy reading books, going for hikes, and trying out new recipes.

• Reading books helps me relax and expand my knowledge.

• Hiking allows me to connect with nature and stay active.

• Trying out new recipes is a creative outlet for me and I enjoy experimenting with different flavors.

ITIL change management is a framework that helps organizations manage and control changes to their IT infrastructure.

• ITIL change management is a part of the IT Infrastructure Library (ITIL) framework.

• It involves the process of requesting, evaluating, approving, and implementing changes to IT systems.

• The goal is to minimize the impact of changes on IT services and ensure they are aligned with business objectives.

• Change management includes documenting change requests, assessing...read more

Use SQL query with subquery to get second highest salary of employee.

• Use ORDER BY clause to sort salaries in descending order

• Use LIMIT 1,1 to get the second row after skipping the first row

• Use a subquery to select the second highest salary

Add digits of an integer using streams.

• Convert the integer to a string

• Split the string into individual characters

• Convert each character back to an integer

• Sum all the integers using streams

GROUP BY is used to group rows that have the same values into summary rows, while HAVING is used to filter groups based on a specified condition.

• GROUP BY is used with aggregate functions to group the result set by one or more columns.

• HAVING is used to filter groups based on a specified condition after the GROUP BY clause.

• GROUP BY is used before the HAVING clause in a query.

• Example: SELECT department, COUNT(*) FROM employees GROUP BY department HAVING COUNT(*) > 5;

Primary key uniquely identifies each record in a table, while Unique key allows only one instance of a value in a column.

• Primary key does not allow NULL values, while Unique key allows one NULL value.

• Primary key automatically creates a clustered index, while Unique key creates a non-clustered index by default.

• Primary key can be referenced by foreign keys, while Unique key cannot be referenced by foreign keys.

Functions return a value, while stored procedures do not. Functions can be used in SELECT statements, stored procedures cannot.

• Functions return a single value, while stored procedures can return multiple values or none at all.

• Functions can be used in SELECT statements to return a value, while stored procedures cannot be used in this way.

• Functions can be called from within stored procedures, but stored procedures cannot be called from within functions.

Double check locking is a design pattern used to prevent multiple threads from creating multiple instances of a singleton class.

• Create a private static instance variable with volatile keyword to ensure visibility across threads

• Use synchronized block inside if condition to check and create instance only once

• Check instance again inside synchronized block to prevent race condition

• Example: private static volatile Singleton instance; public static Singleton getInstance() { if (ins...read more

Procedures are reusable blocks of code that can return values, while functions are named blocks of code that can be called.

• Procedures do not return values, while functions do.

• Functions must return a value, procedures do not have to.

• Functions are called by name, procedures are called by using the CALL statement.

• Functions can be used in SQL queries, procedures cannot.

Control-M Enterprise Manager components play a crucial role in managing and monitoring batch processing workflows.

• Control-M Server: Manages scheduling and monitoring of jobs

• Control-M Agent: Executes jobs on remote servers

• Control-M/EM GUI: Provides a user interface for managing workflows

• Control-M/EM Server: Manages communication between components

• Control-M/EM Reporting Facility: Generates reports on job status and performance

View model in Android is a class that stores and manages UI-related data in a lifecycle-conscious way.

• View model survives configuration changes and is not destroyed when the UI is destroyed.

• It is used to separate the UI controller logic from the UI layout.

• View model is typically used with LiveData to update the UI when the data changes.

• It helps in organizing and handling data for the UI efficiently.

Dependency injection is a design pattern that allows objects to be passed as dependencies rather than being created within a class.

• Types of dependency injection include constructor injection, setter injection, and interface injection.

• Constructor injection involves passing dependencies through a class's constructor.

• Setter injection involves passing dependencies through a class's setter methods.

• Interface injection involves implementing an interface that defines the necessary de...read more

Synechron is a global consulting and technology organization providing innovative solutions to financial services industry.

• Synechron offers services in areas such as digital, business consulting, technology, data science, and blockchain.

• It has a presence in over 18 countries and serves clients in the banking, insurance, capital markets, and digital sectors.

• Synechron has won several awards for its innovative solutions and services, including the Best Use of Emerging or Innovat...read more

Handling waits, frames & windows is crucial for efficient testing in QC Lead role.

• Use explicit waits to handle synchronization issues

• Identify and handle frames by switching to them using frame id or name

• Handle pop-up windows by using window handles and switching between them

• Use implicit waits to set a default waiting time for elements to be available

Event-driven architecture is a design pattern where components communicate through events.

• Components communicate through events

• Decoupled architecture

• Scalable and flexible design

• Examples: message queues, pub/sub systems

Automation testing is the use of software tools to execute tests and compare actual results with expected results.

• Automation testing saves time and effort compared to manual testing.

• It can be used for regression testing, load testing, and performance testing.

• Examples of automation testing tools include Selenium, Appium, and JMeter.

Replicated cache stores copies of data on multiple nodes, while distributed cache partitions data across multiple nodes.

• Replicated cache provides high availability and fault tolerance as data is duplicated on multiple nodes.

• Distributed cache improves scalability and performance by distributing data across multiple nodes.

• In replicated cache, all nodes have a complete copy of the data, which can lead to higher memory requirements.

• In distributed cache, data is divided into parti...read more

The architecture design of my current project involves a microservices-based approach with containerization using Docker and orchestration with Kubernetes.

• Utilizing microservices to break down the application into smaller, independent services

• Implementing containerization with Docker to package and deploy the services

• Leveraging Kubernetes for orchestration to manage and scale the containers efficiently

ConcurrentHashMap is a thread-safe implementation of the Map interface in Java.

• It allows multiple threads to read and write to the map concurrently without any external synchronization.

• It achieves this by dividing the map into segments and locking only the segment being accessed by a thread.

• It provides better performance than synchronized HashMap in multi-threaded environments.

• Example: ConcurrentHashMap map = new ConcurrentHashMap<>();

• map.put("key", 10); int value = map.get("...read more

Thread life cycle refers to the various stages a thread goes through during its execution.

• Thread is created

• Thread is started

• Thread is running

• Thread is blocked

• Thread is terminated

Inheritance is a concept in object-oriented programming where a class can inherit attributes and methods from another class.

• Inheritance allows for code reusability and promotes the concept of hierarchy in programming.

• The class that is being inherited from is called the parent class or superclass, while the class that inherits is called the child class or subclass.

• Child classes can override inherited methods or add new methods and attributes.

• For example, a 'Vehicle' class can ...read more

Encapsulation is the concept of bundling data and methods that operate on the data into a single unit, known as a class.

• Encapsulation helps in hiding the internal state of an object and only exposing the necessary functionalities.

• It allows for better control over the data by preventing direct access from outside the class.

• Encapsulation promotes code reusability and modularity.

• Example: In a class representing a bank account, the account balance should be encapsulated within th...read more

Software Testing Life Cycle involves planning, designing, executing, and reporting on tests to ensure quality software.

• 1. Planning phase involves defining test objectives, scope, and resources.

• 2. Design phase includes creating test cases, test data, and test environment setup.

• 3. Execution phase is where tests are run, defects are logged, and retesting is done.

• 4. Reporting phase involves documenting test results, defects, and overall quality assessment.

• 5. Iterative process wit...read more

CMD is used to provide default arguments for an executing container, while ENTRYPOINT is used to specify the command that will run when the container starts.

• CMD is optional and can be overridden during container runtime

• ENTRYPOINT is required and cannot be overridden during container runtime

• CMD can be used to provide default arguments to the ENTRYPOINT command

Prerequisites of Appium include installing Node.js, Java Development Kit (JDK), Android SDK, and Appium server.

• Install Node.js

• Install Java Development Kit (JDK)

• Install Android SDK

• Install Appium server

row_number, rank, dense_rank are window functions in SQL used to assign a unique number to each row based on specified criteria.

• row_number() assigns a unique sequential integer starting from 1 to each row in the result set

• rank() assigns a unique rank to each row based on the specified ordering criteria, with gaps in ranking for ties

• dense_rank() assigns a unique rank to each row based on the specified ordering criteria, with no gaps in ranking for ties

Smoke testing is a preliminary test to check if the software is stable enough for further testing. Sanity testing is a subset of regression testing to check if the bugs have been fixed and new features have been added without breaking the existing functionality.

• Smoke testing is done to check if the software is stable enough for further testing

• Sanity testing is done to check if the bugs have been fixed and new features have been added without breaking the existing functionalit...read more

Overloading is when a class has multiple methods with the same name but different parameters. Overriding is when a subclass provides its own implementation of a method from its superclass.

• Overloading is used to provide different ways to call a method with different parameters

• Overriding is used to change the behavior of a method in a subclass

• Overloading is resolved at compile-time while overriding is resolved at runtime

• Overloading is also known as compile-time polymorphism whi...read more

HashMap is a data structure that stores key-value pairs and provides constant time complexity for basic operations.

• HashMap uses hashing to store and retrieve elements

• It allows null values and only one null key

• Collisions are resolved using separate chaining or open addressing

• The initial capacity and load factor can be specified during initialization

• The size of the HashMap is dynamically increased as elements are added

Concurrent HashMap is thread-safe and allows concurrent access, while HashMap is not thread-safe.

• Concurrent HashMap is suitable for multi-threaded environments where multiple threads can access and modify the map concurrently.

• HashMap is not thread-safe and can lead to data corruption if accessed concurrently by multiple threads.

• Concurrent HashMap uses internal locking mechanisms to ensure thread safety, while HashMap does not provide such mechanisms.

• Example: In a web applicat...read more

WeakHashMap is a class in Java that provides a hash table implementation with weak keys.

• It is similar to HashMap but allows garbage collection of keys that are no longer referenced.

• It is useful in scenarios where you want to associate additional data with an object without affecting its lifecycle.

• Example: Caching data associated with an object, where the object can be garbage collected when not in use.

Flatten an array without using inbuilt functions

• Create a recursive function to iterate through the array elements

• Check if each element is an array, if so, call the function recursively

• Concatenate the elements into a new array

Machine learning algorithms are used to train models on data to make predictions or decisions.

• Supervised learning algorithms include linear regression, decision trees, and neural networks.

• Unsupervised learning algorithms include clustering and dimensionality reduction.

• Reinforcement learning algorithms involve learning through trial and error.

• Examples of machine learning applications include image recognition, natural language processing, and fraud detection.

Producer-consumer problem is a classic synchronization problem in multithreading.

• Use wait() and notify() methods for synchronization

• Create a shared buffer to store data between producer and consumer

• Ensure proper handling of synchronization to avoid race conditions

Enscribe database is a hierarchical database used for storing large amounts of data.

• Enscribe database is a type of hierarchical database.

• It is used for storing large amounts of data.

• It is commonly used in mainframe environments.

• Enscribe databases are organized into records and fields.

• It supports indexing and querying of data.

• Examples of Enscribe databases include VSAM and IMS DB.

SQL query to retrieve the maximum salary for each department

• Use the MAX() function to find the maximum salary

• Group the results by department using the GROUP BY clause

• Join the employee table with the department table to get the department information

Closure is the process of finalizing or completing something, often used in project management or therapy.

• Closure is important for bringing a sense of completion or resolution to a situation.

• In project management, closure involves wrapping up all loose ends and documenting the project's outcomes.

• In therapy, closure can refer to the process of accepting and moving on from past experiences or relationships.

• Closure can also involve communication or conversation to bring about un...read more

Core Java concepts are fundamental concepts of Java programming language.

• Object-oriented programming

• Inheritance and Polymorphism

• Exception Handling

• Multithreading

• Collections Framework

• Generics

• Lambda Expressions

• Java Virtual Machine (JVM)

• Garbage Collection

• Java API

Delete and truncate are both operations used to remove data, but they differ in their approach and outcome.

• Delete removes entire records or rows from a database, while truncate removes all records from a table

• Delete is slower and can be rolled back, while truncate is faster but cannot be rolled back

• Delete triggers triggers and constraints, while truncate does not

Jenkinsfile is a text file that contains the definition of a Jenkins Pipeline.

• Jenkinsfile is written in Groovy syntax.

• It defines the steps, stages, and configuration of a Jenkins Pipeline.

• It allows for version control and easy sharing of pipeline configurations.

• Jenkinsfile can be stored in a project's repository alongside the code it builds.

Agile framework is a project management approach that emphasizes flexibility, collaboration, and customer satisfaction.

• Agile is iterative and incremental, with frequent feedback loops

• It values individuals and interactions over processes and tools

• It prioritizes working software over comprehensive documentation

• It embraces change and welcomes customer involvement throughout the project

• Examples of Agile frameworks include Scrum, Kanban, and Extreme Programming (XP)

An array in a string is a collection of strings stored in a single variable.

• An array in a string can be created by enclosing multiple strings within square brackets, separated by commas.

• Example: ['apple', 'banana', 'orange']

• Each string in the array can be accessed using its index position.

Multi threading is a technique to execute multiple threads concurrently in a single process.

• Multi threading improves application performance by utilizing multiple CPU cores.

• It requires careful synchronization to avoid race conditions and deadlocks.

• Java provides built-in support for multi threading through the Thread class and Runnable interface.

• Thread pools can be used to manage and reuse threads efficiently.

• Multi threading can be used in various applications such as web serv...read more

Types of joins in SQL are Inner Join, Left Join, Right Join, and Full Join.

• Inner Join: Returns rows when there is a match in both tables.

• Left Join: Returns all rows from the left table and the matched rows from the right table.

• Right Join: Returns all rows from the right table and the matched rows from the left table.

• Full Join: Returns rows when there is a match in one of the tables.

DML commands are Data Manipulation Language commands used to manage data in a database.

• DML commands include INSERT, UPDATE, DELETE, and SELECT.

• INSERT is used to add new rows of data into a table.

• UPDATE is used to modify existing data in a table.

• DELETE is used to remove rows of data from a table.

• SELECT is used to retrieve data from a database.

Execution plan is a roadmap that SQL Server uses to execute a query, showing the steps taken to retrieve data.

• Execution plan is generated by the query optimizer to determine the most efficient way to execute a query.

• It shows the order in which tables are accessed, joins are performed, and filters are applied.

• Execution plan can be viewed using tools like SQL Server Management Studio or by using the EXPLAIN statement in some databases.

Currently working on a project to improve the quality of a mobile banking application.

• Analyzing user feedback to identify common issues

• Creating test cases to ensure all features work as expected

• Collaborating with developers to fix bugs and enhance user experience

ESXi can be patched using vSphere Update Manager or by manually downloading and installing patches.

• Use vSphere Update Manager to scan and remediate hosts

• Download patches from VMware website and install manually using ESXCLI or vSphere CLI

• Ensure compatibility of patches with ESXi version and hardware

• Reboot the host after patch installation

• Monitor patch installation progress and verify successful installation

Scrum is an agile project management framework that emphasizes teamwork, accountability, and iterative progress toward a well-defined goal.

• Scrum is used to manage complex projects

• It involves a team-based approach to project management

• It emphasizes on iterative and incremental progress

• It involves daily stand-up meetings, sprint planning, and sprint reviews

• It promotes transparency, inspection, and adaptation

• Examples of Scrum tools include Jira, Trello, and Asana

Dimensions in SQL are of two types: Fact and Dimension. SQL queries are used to retrieve data from a database.

• Fact dimensions contain numeric values and are used to measure the performance of a business process.

• Dimension tables contain descriptive attributes and are used to filter and group data.

• SQL queries can be used to retrieve data from one or more tables using various clauses like SELECT, FROM, WHERE, GROUP BY, HAVING, and ORDER BY.

• Examples of SQL queries include SELECT ...read more

SQL joins are used to combine rows from two or more tables based on a related column between them.

• Use INNER JOIN to return rows when there is at least one match in both tables

• Use LEFT JOIN to return all rows from the left table and the matched rows from the right table

• Use RIGHT JOIN to return all rows from the right table and the matched rows from the left table

• Use FULL JOIN to return rows when there is a match in one of the tables

A cursor is a database object used to retrieve and manipulate data in a database management system.

• A cursor allows for sequential processing of query results one row at a time.

• It can be used to update or delete specific rows in a result set.

• Cursors are commonly used in stored procedures and triggers.

• Example: DECLARE cursor_name CURSOR FOR SELECT column1, column2 FROM table_name;

Tools used in software development include IDEs, version control systems, testing frameworks, and project management tools.

• Integrated Development Environments (IDEs) such as Eclipse, Visual Studio, and IntelliJ IDEA

• Version control systems such as Git, SVN, and Mercurial

• Testing frameworks such as JUnit, NUnit, and Selenium

• Project management tools such as JIRA, Trello, and Asana

DOM sanitizer in Angular is used to sanitize untrusted HTML to prevent XSS attacks.

• DOM sanitizer is used to sanitize HTML content before rendering it in Angular templates.

• It helps prevent Cross-Site Scripting (XSS) attacks by removing potentially harmful content.

• Angular provides a built-in DomSanitizer service for sanitizing HTML content.

• Example: Using DomSanitizer in Angular template to sanitize a URL before rendering it.

I have experience using tools such as Selenium, JIRA, and TestNG, along with knowledge of Agile and Waterfall methodologies.

• Selenium for automated testing

• JIRA for defect tracking and project management

• TestNG for test case management

• Knowledge of Agile and Waterfall methodologies

Synechron is a leading digital consulting firm with a strong focus on innovation and cutting-edge technology solutions.

• Synechron has a reputation for delivering high-quality digital solutions to clients across various industries.

• The company values innovation and encourages employees to think outside the box.

• Synechron offers opportunities for professional growth and development through training and mentorship programs.

Type in TypeScript refers to the static type of a variable, function, or object.

• Type in TypeScript helps catch errors at compile time by specifying the data type of variables.

• Types in TypeScript include basic types like number, string, boolean, as well as custom types like interfaces and enums.

• Example: let age: number = 25;

An interceptor is a middleware component that intercepts incoming and outgoing HTTP requests in an application.

• Interceptors can be used for logging, authentication, error handling, and modifying requests/responses.

• In Angular, interceptors can be used to modify HTTP requests before they are sent to the server.

• In Spring framework, interceptors can be used to intercept client requests and server responses.

• Interceptors are commonly used in web development to add cross-cutting con...read more

Repartition increases or decreases the number of partitions in a DataFrame, while coalesce only decreases the number of partitions.

• Repartition involves shuffling data across the network, while coalesce tries to minimize shuffling by only creating new partitions if necessary.

• Repartition is typically used when increasing the number of partitions for parallelism, while coalesce is used for decreasing partitions to optimize performance.

• Example: df.repartition(10) vs df.coalesce(5...read more

ETL testing is the process of verifying the accuracy and completeness of data after it has been extracted, transformed, and loaded into a target system.

• ETL testing involves validating data at each stage of the ETL process

• It ensures that data is transformed correctly and loaded into the target system without any errors

• ETL testing also involves checking for data quality and consistency

• Examples of ETL testing tools include Informatica PowerCenter, Talend, and IBM InfoSphere Data...read more

SVG is a vector-based graphics format while Canvas is a bitmap-based graphics format.

• SVG uses XML to define graphics and is resolution-independent.

• SVG elements can be styled with CSS and manipulated with JavaScript.

• Canvas is a pixel-based grid where graphics are drawn programmatically.

• Canvas is more suitable for complex animations and real-time rendering.

• Canvas has better performance for rendering large amounts of data.

End to end recruitment process involves sourcing, screening, interviewing, selecting, and onboarding candidates.

• Sourcing candidates through job portals, social media, referrals, etc.

• Screening resumes and shortlisting candidates based on job requirements

• Conducting interviews and assessments to evaluate candidate skills and fit

• Selecting the best candidate and negotiating salary and benefits

• Onboarding the candidate and ensuring a smooth transition into the company

Program to reverse a string

• Create a char array from the input string

• Use two pointers to swap characters from start and end

• Continue swapping until pointers meet in the middle

Use SQL query with ORDER BY and LIMIT to find second largest salary.

• Use SELECT statement to retrieve the salary column from the table.

• Use ORDER BY clause to sort the salaries in descending order.

• Use LIMIT 1,1 to skip the first highest salary and retrieve the second highest salary.

Java 8 introduced several new features including lambda expressions, streams, and default methods.

• Lambda expressions allow for functional programming and simplify code.

• Streams provide a way to process collections of data in a functional way.

• Default methods allow for adding new methods to interfaces without breaking existing implementations.

• Other features include the Optional class, Date and Time API, and Nashorn JavaScript engine.

A trigger is a special type of stored procedure that automatically executes when certain events occur in a database.

• Triggers can be used to enforce business rules, maintain referential integrity, and automate repetitive tasks.

• Examples of trigger events include INSERT, UPDATE, and DELETE operations on a table.

• Triggers can be defined to execute before or after the triggering event.

There are two types of pipes: named pipes and anonymous pipes.

• Named pipes are used for communication between processes on different computers or on the same computer.

• Anonymous pipes are used for communication between processes on the same computer.

• Named pipes have a unique name and can be accessed by any process that knows the name.

• Anonymous pipes are created by a process and can only be accessed by that process and its child processes.

• Both types of pipes are used for inter-p...read more

Hoisting is a JavaScript mechanism where variables and function declarations are moved to the top of their scope.

• Hoisting applies to variable declarations and function declarations

• Variables declared with var are hoisted to the top of their scope

• Function declarations are hoisted before variables

• Function expressions are not hoisted

• Hoisting can lead to unexpected behavior and should be avoided

Partitioning a large database involves dividing the data into smaller chunks to improve performance and manageability.

• Identify key columns for partitioning, such as date ranges or customer IDs.

• Choose a partitioning strategy, such as range partitioning or hash partitioning.

• Implement partitioning using database features like table partitioning in Oracle or partitioned tables in PostgreSQL.

Collection's framework is a set of interfaces and classes that provide high-performance, high-quality implementations of data structures.

• Provides interfaces like List, Set, Map for storing and manipulating collections of objects

• Includes classes like ArrayList, LinkedList, HashSet, HashMap for concrete implementations

• Allows for easy iteration, sorting, searching, and manipulation of collections

• Supports generics to ensure type safety and compatibility

A palindrome program in Java checks if a given string reads the same forwards and backwards.

• Create a function that takes a string input

• Use a loop to compare characters from both ends of the string

• Return true if the string is a palindrome, false otherwise