100+ Dexco Interview Questions and Answers

Assigning another value to a string reference creates a new string object in memory.

• Assigning a new value to a string reference creates a new string object in memory

• The original string object remains unchanged

• The new value is stored in a different memory location

• The old value may be garbage collected if there are no other references to it

Python is a versatile language with easy syntax, vast libraries, and cross-platform compatibility.

• Python has a simple and readable syntax, making it easy to learn and write code quickly.

• Python has a vast collection of libraries and frameworks for various purposes, such as web development, data analysis, and machine learning.

• Python is cross-platform compatible, meaning that code written on one platform can run on another without modification.

• Python has a large and active commu...read more

Python has several data types including integers, floats, strings, booleans, lists, tuples, dictionaries, and sets.

• Integers represent whole numbers, e.g. 5, -10.

• Floats represent decimal numbers, e.g. 3.14, -2.5.

• Strings represent sequences of characters, e.g. 'hello', 'Python'.

• Booleans represent either True or False.

• Lists are ordered collections of items, e.g. [1, 2, 3].

• Tuples are similar to lists but immutable, e.g. (1, 2, 3).

• Dictionaries are key-value pairs, e.g. {'name': 'J...read more

Lists and arrays in Python are both used to store multiple values, but they have some key differences.

• Lists can store elements of different data types, while arrays can only store elements of the same data type.

• Lists are dynamic in size, meaning they can grow or shrink as needed, while arrays have a fixed size.

• Lists have built-in methods for manipulation and iteration, while arrays require the use of external libraries like NumPy for similar functionality.

Constructors in Python are special methods used to initialize objects. They are called automatically when an object is created.

• Constructors have the same name as the class they belong to.

• They are defined using the __init__() method.

• Constructors can take arguments to initialize instance variables.

• If a class does not have a constructor, Python provides a default constructor.

• Constructors can also be used to perform any other setup tasks needed for the object.

Building blocks of OOP include encapsulation, inheritance, and polymorphism.

• Encapsulation: bundling data and methods that operate on that data within a single unit

• Inheritance: creating new classes from existing ones, inheriting their properties and methods

• Polymorphism: ability of objects to take on many forms, allowing for flexibility and extensibility

• Examples: class, object, method, constructor, interface, abstract class

Joins in SQL are used to combine data from two or more tables based on a related column.

• Inner join returns only the matching rows from both tables.

• Left join returns all the rows from the left table and matching rows from the right table.

• Right join returns all the rows from the right table and matching rows from the left table.

• Full outer join returns all the rows from both tables.

• Real world applications include combining customer and order data, employee and salary data, and p...read more

The finally block will always execute, even if an exception is thrown from the try block.

• The finally block is used to execute code that should always run, regardless of whether an exception is thrown or not.

• If an exception is thrown from the try block, the code in the finally block will still execute.

• This is useful for cleaning up resources, such as closing files or database connections.

• Example: try { // code that may throw an exception } finally { // code that should always ...read more

Slicing a list means extracting a portion of the list. Syntax: list[start:end:step]

• Start index is inclusive, end index is exclusive

• If start is not specified, it defaults to 0

• If end is not specified, it defaults to the end of the list

• If step is not specified, it defaults to 1

• Negative indices count from the end of the list

Yes, Python has a destructor called __del__()

• The __del__() method is called when an object is about to be destroyed

• It is used to perform cleanup operations before the object is destroyed

• The __del__() method is not guaranteed to be called in all cases

Indexes in SQL are used to improve query performance by allowing faster data retrieval.

• Indexes are data structures that provide quick access to data in a table.

• They are created on one or more columns of a table.

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

• Clustered indexes determine the physical order of data in a table, while non-clustered indexes are separate structures that point to the data.

• Unique indexes ensure that each value in the i...read more

Python has four types of values: integers, floating-point numbers, strings, and booleans.

• Integers are whole numbers, positive or negative, such as 5 or -10.

• Floating-point numbers are decimal numbers, such as 3.14 or -2.5.

• Strings are sequences of characters, enclosed in single or double quotes, such as 'hello' or "world".

• Booleans are either True or False, used for logical operations.

To get unique values from a collection using stream, use the distinct() method.

• Call the distinct() method on the stream of the collection.

• The distinct() method returns a stream of unique elements.

• Use the collect() method to convert the stream back to a collection.

Split() & Join() are string methods used to split a string into an array and join an array into a string respectively.

• Split() method is used to split a string into an array of substrings based on a specified separator.

• Join() method is used to join the elements of an array into a string using a specified separator.

• Both methods are commonly used in data processing and manipulation tasks.

• Example: var str = 'apple,banana,orange'; var arr = str.split(','); // ['apple', 'banana', '...read more

Global and local variables are used in Python to store values. Global variables can be accessed from anywhere in the code, while local variables are only accessible within a specific function.

• Global variables are declared outside of any function and can be accessed from anywhere in the code

• Local variables are declared within a function and can only be accessed within that function

• Global variables can be modified from within a function using the 'global' keyword

• Local variables...read more

Python has several built-in datatypes including int, float, bool, str, list, tuple, set, and dict.

• int: used for integers, e.g. 5, -10

• float: used for floating-point numbers, e.g. 3.14, -2.5

• bool: used for boolean values, True or False

• str: used for strings, e.g. 'hello', 'world'

• list: used for ordered collections of items, e.g. [1, 2, 3]

• tuple: used for ordered collections of items that cannot be changed, e.g. (1, 2, 3)

• set: used for unordered collections of unique items, e.g. {1, ...read more

To delete a file in Python module, use the os module's remove() method.

• Import the os module

• Use the remove() method to delete the file

• Specify the file path in the remove() method

Literals are fixed values while variables can hold different values during program execution.

• Literals are hardcoded values in code, like 'hello' or 42

• Variables are containers that can hold different values during program execution

• Variables can be assigned literals or other variables

• Variables can be used to store and manipulate data

• Literals cannot be changed during program execution

Flask and Django are popular python frameworks for web development.

• Flask is a micro web framework that is easy to learn and use.

• Django is a full-stack web framework that provides many built-in features.

• Other frameworks include Pyramid, Bottle, and Tornado.

• Flask and Django both use the WSGI standard for serving web applications.

• Flask is often used for small to medium-sized projects, while Django is better suited for larger projects.

• Flask allows for more flexibility and customi...read more

Joins in SQL are used to combine data from two or more tables based on a related column.

• Inner join returns only the matching rows from both tables.

• Left join returns all the rows from the left table and matching rows from the right table.

• Right join returns all the rows from the right table and matching rows from the left table.

• Full outer join returns all the rows from both tables.

• Example: Inner join can be used to combine customer and order tables based on customer ID.

Function overloading is defining multiple functions with the same name but different parameters. Operator overloading is defining operators to work with user-defined types.

• Function overloading allows a function to perform different operations based on the number, type, and order of parameters.

• Operator overloading allows operators such as +, -, *, /, etc. to work with user-defined types.

• Function overloading is resolved at compile-time while operator overloading is resolved at ...read more

Python iterators are objects that allow iteration over a collection of elements.

• Iterators are used to access elements of a collection sequentially.

• They are implemented using the __iter__() and __next__() methods.

• The __iter__() method returns the iterator object and the __next__() method returns the next element in the collection.

• Iterators can be used with loops, comprehensions, and other iterable functions.

• Examples of built-in iterators in Python include range(), enumerate(),...read more

Multi role login system can be managed by assigning different access levels to each role.

• Create a database table for roles and their access levels

• Assign each user a role with corresponding access level

• Implement role-based access control (RBAC) to restrict access to certain features

• Use session management to keep track of user roles

• Provide an admin panel to manage roles and access levels

The '==' operator compares the reference of objects, while the 'equals' method compares the content of objects.

• The '==' operator checks if two objects refer to the same memory location.

• The 'equals' method compares the content of objects based on their implementation.

• The 'equals' method can be overridden to provide custom comparison logic.

• Example: String str1 = new String('hello'); String str2 = new String('hello'); str1 == str2 will be false, but str1.equals(str2) will be tru...read more

init() method is a constructor in Python that initializes an object when it is created.

• It is called automatically when an object is created.

• It takes self as the first parameter.

• It can be used to initialize instance variables.

• It can also take additional parameters.

• Example: def __init__(self, name, age): self.name = name; self.age = age

Pass by value and pass by reference are two ways of passing arguments to a function.

• Pass by value means that a copy of the argument is passed to the function.

• Pass by reference means that a reference to the argument is passed to the function.

• In pass by value, any changes made to the argument inside the function do not affect the original value.

• In pass by reference, any changes made to the argument inside the function affect the original value.

• Pass by value is used for simple d...read more

Test with priority 1 executes first, followed by 0 and then -1.

• Tests with higher priority are executed first

• Priority can be used to determine the order of execution

• Priority can be set in test management tools like JIRA or TestRail

The @Component annotation is a generic stereotype annotation that can be used in place of other annotations.

• The @Component annotation is a general-purpose annotation that can be used in place of @Service, @Controller, @Configuration, and @Repository annotations.

• However, using more specific annotations can help in better understanding the role of the annotated class.

• For example, using @Service annotation on a class that provides a service makes it easier to understand the purp...read more

To take multiple values from dropdown, use a loop to iterate through each option and select them.

• Identify the dropdown element using its locator

• Use the Select class to create an object for the dropdown

• Use the getOptions() method to get all the options in the dropdown

• Iterate through the options using a loop and select each option using the selectByVisibleText() or selectByValue() method

Delivering a release in Agile Scrum involves continuous integration and delivery. Monolith, multitenant, and microservices differ in architecture. Kafka is a distributed streaming platform. Conflict resolution and managing client expectations are crucial skills.

• Agile Scrum involves continuous integration and delivery

• Monolith is a single, self-contained application, multitenant serves multiple clients, and microservices are independent components

• Kafka is a distributed streamin...read more

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

• SQL stands for Structured Query Language.

• It is used to create, modify, and query databases.

• SQL is used in various industries such as finance, healthcare, and e-commerce.

• Examples of SQL-based databases include MySQL, Oracle, and Microsoft SQL Server.

Determines if words in given array are anagram or not using JS

• Create a function that takes an array of strings as input

• Loop through the array and sort each string alphabetically

• Compare the sorted strings to check if they are equal

• Return true if all strings are anagrams, else false

Lambda expression is an anonymous function while method reference refers to an existing method

• Lambda expression is used to create an instance of a functional interface

• Method reference is used to refer to an existing method of a class or object

• Lambda expression uses the arrow operator (->) to separate the parameters and the body

• Method reference uses the double colon (::) operator to separate the class or object and the method name

To delete a file in Python module, use the os module's remove() method.

• Import the os module

• Use the remove() method to delete the file

• Specify the file path in the remove() method

• Example: import os; os.remove('file.txt')

Remove duplicate entries from array of strings using JavaScript

• Use Set to remove duplicates

• Convert Set back to array

• Use spread operator to convert Set to array

ElementNotPresent exception occurs even if element is present on page. Why?

• The element may not be loaded yet, so wait for it to load before checking

• The element may be hidden or not visible on the page

• The element may have a different name or ID than expected

• The element may be in an iframe or shadow DOM

• The element may have been removed or deleted from the page

Answers to common Java interview questions

• public static void main is the entry point of a Java program

• System.out.println prints to standard output while System.err.println prints to standard error

• An interface is a collection of abstract methods that can be implemented by a class

• Use an abstract class when you want to provide a default implementation or when you need to inherit from multiple classes

• Public methods can be accessed from anywhere while protected methods can only be...read more

Yes, Python has a destructor called __del__().

• The __del__() method is called when an object is about to be destroyed.

• It is used to perform cleanup operations before the object is destroyed.

• The __del__() method is not guaranteed to be called, so it should not be relied upon for critical cleanup operations.

JIT compiler stands for Just-In-Time compiler. It dynamically compiles code during runtime for improved performance.

• JIT compiler translates bytecode into machine code at runtime

• It optimizes code execution by identifying frequently executed code and compiling it

• Examples include the JIT compilers used in Java Virtual Machine (JVM) and .NET Common Language Runtime (CLR)

CSS methods for fixed headers and footers

• Use position: fixed property

• Set top or bottom property to 0 for fixed header/footer

• Add z-index property to ensure header/footer is on top

• Consider using padding or margin to avoid overlapping content

Set and list are both collection types in Java. Vector and ArrayList are two implementations of List interface.

• Set is an unordered collection of unique elements while List is an ordered collection of elements.

• Collections hierarchy in Java includes Collection interface, List interface, Set interface, and Map interface.

• Vector is a synchronized implementation of List interface while ArrayList is not synchronized.

• Arrays are fixed in size while ArrayLists can grow dynamically.

• Exam...read more

Indexes in SQL are used to improve query performance by allowing faster data retrieval.

• Indexes are data structures that store a small portion of the table data in an easily searchable format.

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

• Clustered indexes determine the physical order of data in a table, while non-clustered indexes create a separate structure for faster searching.

• Unique indexes ensure that no two rows in a table have the same ...read more

Python is a high-level, interpreted programming language known for its simplicity, readability, and ease of use.

• Python is dynamically typed, meaning that variable types are determined at runtime.

• Python has a large standard library and a vast collection of third-party libraries.

• Python is often used for web development, scientific computing, data analysis, and artificial intelligence.

• Python code is typically shorter and more concise than code in other languages.

• Python is slower...read more

I am familiar with HTML, CSS, and JavaScript for front-end development.

• HTML

• CSS

• JavaScript

Python uses a dynamic memory allocation technique called reference counting.

• Python uses a heap data structure to store objects.

• Objects are created dynamically and stored in memory.

• Python uses a garbage collector to free up memory that is no longer being used.

• Python also uses a technique called memory pooling to reuse memory for small objects.

• Python supports both mutable and immutable objects, which affects how memory is allocated and managed.

Fail fast and fail safe are two error handling techniques in Java.

• Fail fast approach detects errors as early as possible and stops the program execution immediately.

• Fail safe approach handles errors gracefully and continues program execution.

• Examples of fail fast include NullPointerException and ArrayIndexOutOfBoundsException.

• Examples of fail safe include using try-catch blocks and logging errors instead of throwing exceptions.

Variables are containers that store values while literals are values themselves.

• Variables can be changed while literals cannot

• Variables can be assigned to literals

• Literals are used to represent fixed values

• Variables are used to represent changing values

The building blocks of object oriented programming are classes, objects, inheritance, encapsulation, and polymorphism.

• Classes are templates for creating objects

• Objects are instances of classes

• Inheritance allows classes to inherit properties and methods from parent classes

• Encapsulation is the practice of hiding implementation details from users

• Polymorphism allows objects to take on multiple forms

Operator overloading is the ability to redefine operators for user-defined types. Function overloading is the ability to define multiple functions with the same name but different parameters.

• Operator overloading allows user-defined types to use operators such as +, -, *, /, etc.

• Function overloading allows multiple functions to have the same name but different parameters.

• Operator overloading and function overloading both provide a way to make code more readable and intuitive.

• E...read more

Program to print even and odd numbers up to 10 using two threads.

• Create two threads, one for even numbers and one for odd numbers.

• Use a loop to iterate through numbers 1 to 10.

• In each iteration, check if the number is even or odd.

• If the number is even, print it using the even thread.

• If the number is odd, print it using the odd thread.

Data binding in Angular is a way to establish a connection between the UI and the application's data.

• Data binding allows automatic synchronization of data between the model and the view.

• It eliminates the need for manual DOM manipulation.

• There are different types of data binding in Angular, such as interpolation, property binding, event binding, and two-way binding.

• Interpolation: {{ data }}

• Property binding: [property]='data'

• Event binding: (event)='handler()'

• Two-way binding: [(...read more

Modules in Python are files containing Python code that can be imported and used in other Python programs.

• Modules are used to organize and reuse code in Python.

• They allow for better code organization and maintainability.

• Modules can be imported using the 'import' statement.

• Python provides a wide range of built-in modules, such as 'math' and 'random'.

• Custom modules can also be created to encapsulate related functionality.

AWS tier architecture includes Load Balancer for distributing traffic and S3 for scalable storage.

• AWS tier architecture consists of multiple layers such as presentation, application, and data tiers.

• Load Balancer helps distribute incoming traffic across multiple instances to ensure optimal resource utilization and prevent overload.

• S3 (Simple Storage Service) is a scalable storage solution offered by AWS for storing and retrieving data.

• S3 allows for easy management of data thro...read more

Python literals are fixed values that are used to represent data in code.

• Literals can be of various types such as string, integer, float, boolean, etc.

• They are used to assign values to variables or as arguments in functions.

• Examples of literals include 'hello world' (string), 42 (integer), 3.14 (float), True (boolean), etc.

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

• It allows multiple threads to access and modify the map concurrently without any external synchronization.

• It achieves this by dividing the map into segments, each of which can be locked independently.

• It provides better performance than synchronized HashMap for concurrent access.

• It is part of the java.util.concurrent package in Java.

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

Yes, we can update a tuple in a list of tuples. However, tuples are immutable, so we need to create a new tuple.

• To update a tuple in a list of tuples, we can convert the tuple to a list, update the desired element, and then convert it back to a tuple.

• For example, if we have a list of tuples called 'list_of_tuples' and we want to update the second tuple, we can do: list_of_tuples[1] = tuple(updated_list)

• Similarly, we can update a tuple in a tuple of lists by converting the inn...read more

Python generators are functions that return an iterator object which can be iterated over to produce a sequence of values.

• Generators are defined using the 'yield' keyword instead of 'return'.

• They allow for lazy evaluation, generating values on-the-fly instead of all at once.

• Generators can be used to generate an infinite sequence of values.

• They are memory efficient as they do not store the entire sequence in memory.

• Example: def my_generator(): yield 1; yield 2; yield 3;

• Example...read more

Scheduled script runs on a predefined schedule, while Map reduce script processes large datasets in parallel.

• Scheduled script is used for automating tasks at specific times, like sending reports daily at 8am.

• Map reduce script is used for processing large datasets by splitting them into smaller chunks and processing them in parallel.

• Scheduled script is typically used for routine tasks, while Map reduce script is used for data processing and analysis.

• Scheduled script is often u...read more

Yes, finally block will execute even if try and catch have return statement.

• The finally block is always executed regardless of whether an exception is thrown or not.

• The return statement in try or catch block will be executed before the finally block.

• Finally block is commonly used to release resources or perform cleanup operations.

Polymorphism is the ability of an object to take on many forms.

• Polymorphism allows objects of different classes to be treated as if they are of the same class.

• It is achieved through method overriding and method overloading.

• Example: A parent class Animal can have child classes like Dog, Cat, and Cow, each with their own unique implementation of the method 'makeSound'.

• Polymorphism makes code more flexible and reusable.

Merge multiple sorted arrays into one sorted array

• Merge all arrays into one array

• Sort the merged array

• Return the sorted array

Composer is a dependency manager for PHP. Drupal can be updated through composer using the command line.

• Composer is used to manage dependencies in PHP projects

• To update Drupal using composer, run the command 'composer update drupal/core --with-dependencies'

• Composer.lock file should be committed to version control

Hashmap and Hashset are data structures used to store key-value pairs and unique values respectively.

• Hashmap uses hashing to store key-value pairs in an array. The hash function is used to map the key to an index in the array.

• Hashset is similar to Hashmap but only stores unique values. It uses hashing to store values in an array.

• Both Hashmap and Hashset have constant time complexity for insertion, deletion, and retrieval operations.

• Hashmap allows null values and one null key,...read more

Migration projects involve moving data, applications, or infrastructure from one system to another.

• Migration of data from on-premises servers to cloud storage

• Upgrading software versions and transferring data to new systems

• Moving applications from one platform to another, such as from Windows to Linux

• Consolidating multiple databases into a single system

Sleep pauses the execution of a thread for a specified time, while wait pauses the execution until a specific condition is met.

• Sleep is a static method of the Thread class, while wait is an instance method of the Object class.

• Sleep is used to introduce a delay in the execution of a thread, while wait is used to wait for a specific condition to be met.

• Sleep releases the lock on the object, while wait does not release the lock.

• Sleep can be interrupted by another thread, while w...read more

Failed test screenshots can be taken using automation tools and saved in a designated folder.

• Use automation tools like Selenium or Appium to capture screenshots on test failure

• Save the screenshots in a designated folder for easy access and reference

• Include the screenshot file name in the test report for better traceability

Static service in Angular is used to share data between components and persists data even after the component is destroyed.

• Static service is a singleton service that can be injected into any component.

• It is used to share data between components.

• Data persists even after the component is destroyed.

• It is useful for sharing data between sibling components.

• Example: a shopping cart service that persists the cart data across different pages.

Python has five standard data types: Numbers, Strings, Lists, Tuples, and Dictionaries.

• Numbers include integers, floating-point numbers, and complex numbers.

• Strings are sequences of Unicode characters.

• Lists are ordered sequences of values.

• Tuples are ordered, immutable sequences of values.

• Dictionaries are unordered collections of key-value pairs.

init() method is a constructor method in Python that is called when an object is created.

• It initializes the attributes of the object.

• It takes self as the first parameter.

• It can be used to perform any setup required before the object is used.

• It can be overridden to customize the initialization process.

• Example: def __init__(self, name, age): self.name = name self.age = age

Global variables are accessible throughout the program, while local variables are only accessible within a specific function.

• Global variables are declared outside of any function and can be accessed from any part of the program.

• Local variables are declared within a function and can only be accessed within that function.

• If a local variable has the same name as a global variable, the local variable takes precedence within the function.

• Global variables can be modified from withi...read more

Our automation framework is built using Selenium WebDriver and TestNG.

• We use Page Object Model design pattern for better maintainability.

• We have created custom libraries for common functions like login, logout, etc.

• We use Jenkins for continuous integration and execution of automated tests.

• We have implemented data-driven testing using Excel sheets.

• We use Git for version control and collaboration among team members.

Alerts can be handled using Alert interface in Selenium

• Use driver.switchTo().alert() method to switch to alert

• Use getText() method to get the text of the alert

• Use accept() method to click on OK button of the alert

• Use dismiss() method to click on Cancel button of the alert

Generative AI and NLP are advanced technologies used to create content and understand human language.

• Generative AI involves creating new content, such as images, music, or text, using algorithms like GANs.

• NLP focuses on understanding and generating human language, used in chatbots, sentiment analysis, and language translation.

• Use cases of Generative AI include deepfake videos, art generation, and text generation.

• NLP is used in virtual assistants like Siri, language translatio...read more

Key topics in Generative AI include Retrieval-Augmented Generation (RAG) and Large Language Models (LLM).

• RAG combines generative models with retrieval mechanisms to improve text generation.

• LLMs like GPT-3 and BERT are pre-trained on large text corpora to generate human-like text.

• Ethical considerations in using LLMs for text generation, such as bias and misinformation.

• Applications of RAG and LLMs in natural language processing tasks like chatbots, summarization, and translatio...read more

TestNG annotations are executed in a specific sequence during test execution.

• BeforeSuite

• BeforeTest

• BeforeClass

• BeforeMethod

• Test

• AfterMethod

• AfterClass

• AfterTest

• AfterSuite

Concurrent hashmap allows multiple threads to access and modify the map concurrently.

• Concurrent hashmap is thread-safe and uses internal locking mechanisms to ensure consistency.

• It uses a technique called 'lock striping' to divide the map into multiple segments, each with its own lock.

• This allows multiple threads to access different segments of the map concurrently without blocking each other.

• Concurrent hashmap also uses a technique called 'resizing' to dynamically adjust the...read more

The answer to the question is a Python function that finds all occurrences of a given substring in a string and returns the count.

• Use the `count()` method to find the count of occurrences of a substring in a string.

• Iterate through the string and use slicing to check for occurrences of the substring.

• Store the occurrences and their counts in a dictionary or a list of tuples.

Iterator is a general interface while ListIterator is specific to List interface.

• Iterator can traverse any collection while ListIterator can traverse only List.

• ListIterator can traverse in both directions while Iterator can traverse only forward.

• ListIterator has additional methods like add(), set(), previous(), etc.

• Iterator is used for read-only access while ListIterator is used for both read and write access.

Serialization is the process of converting an object into a stream of bytes to store or transmit it.

• Java provides Serializable interface to enable serialization of objects.

• Serialization can be used for caching, deep cloning, and remote method invocation.

• Deserialization is the process of converting a stream of bytes back into an object.

• Java also provides Externalizable interface for custom serialization.

• Serialization can be controlled using transient and static fields.

Multiple databases can be connected to Drupal using the Database API and configuring settings.php file.

• Use the Database API to connect to additional databases

• Add the database connection details to settings.php file

• Use the db_set_active() function to switch between databases

• Use the db_query() function to execute queries on the selected database

Shallow copy and Deep copy in Python Difference and how to use?

• Shallow copy creates a new object but references the original object's memory address

• Deep copy creates a new object with a new memory address and copies the original object's values

• Shallow copy can be done using slicing, copy() method, or the built-in list() function

• Deep copy can be done using the deepcopy() method from the copy module

• Shallow copy is faster and uses less memory, but changes to the original object ...read more

Python has two types of constructors - default and parameterized constructors.

• Default constructor has no parameters and is automatically called when an object is created.

• Parameterized constructor takes parameters and is used to initialize the object's attributes.

• Example of default constructor: def __init__(self):

• Example of parameterized constructor: def __init__(self, name, age):

Python uses automatic memory management through garbage collection.

• Python uses reference counting to keep track of memory usage.

• Objects with no references are automatically deleted by the garbage collector.

• Python also has a built-in module called 'gc' for manual garbage collection.

• Memory leaks can occur if circular references are not handled properly.

Software development life cycle is a process followed by software developers to design, develop and maintain software.

• SDLC consists of several phases such as planning, analysis, design, implementation, testing, deployment, and maintenance.

• Each phase has its own set of activities and deliverables.

• SDLC models include Waterfall, Agile, and DevOps.

• SDLC helps in ensuring that the software is developed efficiently, meets the requirements, and is of high quality.

• SDLC also helps in r...read more

I rate myself as proficient in programming languages with experience in Java, Python, and C++.

• Proficient in Java, Python, and C++

• Experience in developing applications using these languages

• Familiarity with various frameworks and libraries

• Ability to write efficient and optimized code

• Experience in debugging and troubleshooting

• Continuously learning and improving skills

I have a strong understanding of the existing project and the technology stacks used.

• The existing project is a data analytics platform used for analyzing customer behavior and making data-driven decisions.

• The technology stacks used include Python for data processing, SQL for database management, and Tableau for data visualization.

• I have experience working with machine learning algorithms such as regression, classification, and clustering in this project.

Object-oriented programming concepts that help in organizing and designing code for reusability and maintainability.

• Encapsulation: Bundling data and methods that operate on the data into a single unit (class).

• Inheritance: Ability of a class to inherit properties and behavior from another class.

• Polymorphism: Ability to present the same interface for different data types.

• Abstraction: Hiding the complex implementation details and showing only the necessary features to the user.

ACID properties are a set of properties that guarantee the reliability of database transactions.

• ACID stands for Atomicity, Consistency, Isolation, and Durability

• Atomicity ensures that all operations in a transaction are completed successfully or none at all

• Consistency ensures that the database remains in a consistent state before and after the transaction

• Isolation ensures that multiple transactions can run concurrently without affecting each other

• Durability ensures that once ...read more

Split method splits a string into an array of substrings based on a specified separator. Join method joins the elements of an array into a string.

• Split method returns an array of strings.

• Join method concatenates the elements of an array into a string.

• Both methods are used to manipulate strings in JavaScript.

• Example: var str = 'apple,banana,orange'; var arr = str.split(','); var newStr = arr.join('-');

• Output: arr = ['apple', 'banana', 'orange'], newStr = 'apple-banana-orange'

I have worked with Azure App Services, Azure Functions, Azure SQL Database, and Azure Blob Storage.

• Azure App Services for hosting web applications

• Azure Functions for serverless computing

• Azure SQL Database for relational database management

• Azure Blob Storage for storing unstructured data

To check if any job failed, we can use monitoring tools and logs. ITIL recommends incident management process.

• Use monitoring tools like Nagios, Zabbix, etc. to check job status

• Check logs for any error messages or exceptions

• ITIL recommends following the incident management process to resolve the issue

• Incident management process includes identifying, logging, categorizing, prioritizing, diagnosing, resolving, and closing the incident

A nested list is a list that contains other lists as its elements.

• Nested lists can be created using square brackets and separating the elements with commas.

• Elements of a nested list can be accessed using indexing and slicing.

• Example: my_list = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]

• Accessing element 5: my_list[1][1]

Custom modules and themes can be created in Drupal using PHP and CSS/HTML respectively.

• To create a custom module, define a .info.yml file, a .module file, and a .routing.yml file.

• To create a custom theme, define a .info.yml file, a .theme file, and a .libraries.yml file.

• Use Drupal's hook system to add functionality to your module.

• Use Twig templates to customize the HTML/CSS of your theme.

• Use Drupal's theming functions to add dynamic content to your theme.

• Examples of custom mo...read more

Object-oriented programming paradigm focusing on objects and classes for code organization and reusability.

• Encapsulation: Bundling data and methods that operate on the data into a single unit (class)

• Inheritance: Ability of a class to inherit properties and behavior from another class

• Polymorphism: Ability to present the same interface for different data types

An interface in software engineering is a contract that defines the methods that a class must implement.

• Interfaces in Java are used to achieve abstraction and multiple inheritance.

• Interfaces contain only method signatures, not method bodies.

• Classes can implement multiple interfaces in Java.

• Interfaces are used to define the behavior of a class without specifying how that behavior is implemented.

A queue is a data structure that follows the First In First Out (FIFO) principle.

• Elements are added to the back of the queue and removed from the front.

• Example: A line of people waiting for a movie ticket.

• Operations: Enqueue (add element to back), Dequeue (remove element from front), Peek (view front element)

No, we cannot use == to compare enums.

• Enums are objects and == compares object references, not values.

• We should use .equals() method to compare enum values.

Python modules are files containing Python code that can be imported and used in other Python programs.

• Modules are used to organize code into reusable and maintainable structures.

• Python has a large standard library of modules that can be imported and used.

• Third-party modules can also be installed and used in Python programs.

• Modules can define functions, classes, and variables that can be accessed by other modules.

• Modules can be imported using the 'import' statement in Python.

To switch default frame in automation testing, use switchTo() method of WebDriver class.

• Use driver.switchTo().frame() method to switch to a specific frame by index, name, or WebElement.

• Use driver.switchTo().defaultContent() method to switch back to the default content.

• Example: driver.switchTo().frame(0); //switch to first frame

• Example: driver.switchTo().frame("frameName"); //switch to frame with name "frameName"