Centroxy Solution Interview Questions, Process, and Tips

Indexing in SQL is a way to optimize the performance of queries by creating a data structure that allows for faster retrieval of data.

• Indexes are created on columns in a database table to speed up the retrieval of rows that match a certain condition in a WHERE clause.

• Indexes can be created using CREATE INDEX statement in SQL.

• Types of indexes include clustered indexes, non-clustered indexes, unique indexes, and composit...read more

Primary index is the main index used to uniquely identify records in a database, while secondary index is an additional index for faster access to specific data.

• Primary index is typically based on the primary key of a table, ensuring uniqueness of each record.

• Secondary index is created on non-primary key columns to improve query performance for specific data retrieval.

• Example: In a student database, student ID can be a...read more

Table Lock in SQL is a mechanism that prevents other users from accessing a table while it is being used by a transaction.

• Table Lock is used to control access to a table in a database.

• It can be used to prevent other users from reading or writing to a table while a transaction is in progress.

• There are different types of table locks such as shared lock, exclusive lock, and update lock.

• Table locks can impact the performan

Maintain security in Web API by implementing authentication, authorization, encryption, and input validation.

• Implement authentication mechanisms such as OAuth, JWT, or API keys to verify the identity of clients accessing the API.

• Use authorization to control access to resources based on roles and permissions.

• Encrypt sensitive data using SSL/TLS to ensure secure communication between clients and the API.

• Validate and sani...read more

OOP (Object-Oriented Programming) is a programming paradigm based on objects and classes, promoting code reusability and modularity.

• Encapsulation: Bundling data and methods that operate on the data within one unit (e.g., a class).

• Inheritance: Mechanism to create a new class using properties and methods of an existing class (e.g., a 'Dog' class inheriting from an 'Animal' class).

• Polymorphism: Ability to present the same...read more