Fintouch Consultancy Services Software Developer Interview Questions and Answers

Object-oriented programming concepts that focus on classes, objects, inheritance, encapsulation, and polymorphism.

• Classes: Blueprint for creating objects with attributes and methods.

• Objects: Instances of classes that contain data and behavior.

• Inheritance: Ability for a class to inherit attributes and methods from another class.

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

• Polymorp...read more

Status codes in API are standardized codes returned by a server in response to a client's request.

• Status codes indicate the outcome of the request (e.g. success, error, redirection)

• Common status codes include 200 (OK), 404 (Not Found), 500 (Internal Server Error)

• Status codes are grouped into different categories (e.g. 2xx for success, 4xx for client errors, 5xx for server errors)

Joins are generally faster than subqueries.

• Joins are typically faster than subqueries because they allow the database to retrieve data in a more efficient manner.

• Subqueries can be slower because they are executed for each row of the outer query, leading to potential performance issues.

• However, the performance can vary depending on the specific query and database optimization.

• In general, it is recommended to use joins o...read more

Token is a unique identifier used for authentication, while refresh token is used to obtain a new access token.

• Token is a unique string that is used to authenticate a user or device.

• Refresh token is used to obtain a new access token after the original token expires.

• Tokens are commonly used in OAuth authentication.

• Example: Access token: eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9. Refresh token: eyJhbGciOiJIUzI1NiIsInR5cCI6Ikp...read more

DI in dotnet core stands for Dependency Injection, a design pattern used to achieve loose coupling between components.

• DI allows for injecting dependencies into a class rather than creating them within the class itself.

• It helps in achieving separation of concerns and makes the code more testable and maintainable.

• Example: In dotnet core, services can be registered in the Startup class and injected into controllers or oth...read more

Isolation in SQL refers to the ability to control the visibility of changes made by one transaction to other transactions.

• Isolation levels in SQL determine how transactions interact with each other

• Higher isolation levels provide more control over visibility of changes

• Common isolation levels include READ UNCOMMITTED, READ COMMITTED, REPEATABLE READ, and SERIALIZABLE