Entrata Interview Questions, Process, and Tips

Abstract class can have both abstract and non-abstract methods, while interface can only have abstract methods.

• Abstract class can have constructors, fields, and methods, while interface cannot have any of these.

• A class can implement multiple interfaces but can only inherit from one abstract class.

• Abstract classes are used to provide a common base for multiple classes, while interfaces are used to define a contract for ...read more

OOP Concepts refer to the principles of Object-Oriented Programming, including encapsulation, inheritance, polymorphism, and abstraction.

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

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

• Polymorphism: The ability for objects of different classes to respond to the same message in different ways...read more

Database queries involve retrieving, updating, and manipulating data stored in a database.

• Database queries are used to retrieve specific data from a database based on certain criteria.

• Queries can also be used to update existing data or insert new data into the database.

• SQL (Structured Query Language) is commonly used to write database queries.

• Examples of database queries include SELECT, INSERT, UPDATE, and DELETE state

The final class and method are used to prevent inheritance and method overriding respectively.

• Final class: A final class cannot be subclassed. It is often used for utility classes or classes that should not be extended.

• Final method: A final method cannot be overridden by subclasses. It is used to prevent modification of a method's behavior in subclasses.

Find duplicate numbers in an array of strings.

• Iterate through the array and keep track of the count of each number using a hash map.

• If the count of a number is greater than 1, it is a duplicate.

• Return the list of duplicate numbers.

The output will be the literal string of the variable, without any variable interpolation.

• When a variable is echoed in single quotes, it is treated as a literal string.

• No variable interpolation or special characters are interpreted.

• The output will include the variable name itself, not its value.

Object-oriented programming (OOP) is a programming paradigm that uses objects to represent and manipulate data.

• OOP is based on the concept of classes and objects.

• It focuses on encapsulation, inheritance, and polymorphism.

• Encapsulation hides the internal details of an object and provides a public interface.

• Inheritance allows classes to inherit properties and methods from other classes.

• Polymorphism allows objects of diff...read more

The HAVING clause is used in MySQL to filter the results of a GROUP BY query based on a condition.

• The HAVING clause is similar to the WHERE clause, but it operates on grouped rows rather than individual rows.

• It is used in conjunction with the GROUP BY clause.

• The HAVING clause is used to filter the results of a GROUP BY query based on a condition that applies to the grouped rows.

• It is typically used to specify condition...read more