HDFC Bank Interview Questions and Answers

OOPS is a programming paradigm based on objects and classes. Java doesn't support multi-level inheritance to avoid ambiguity and complexity.

• OOPS stands for Object-Oriented Programming System, where programs are organized around objects rather than actions.

• Java supports single inheritance, where a class can only inherit from one superclass to avoid the diamond problem.

• Multi-level inheritance in Java can lead to ambiguity and complexity, as a subclass can inherit properties fro...read more

DB consistency in multi-threading ensures that data remains accurate and up-to-date across multiple threads.

• Use transactions to ensure atomicity and isolation of database operations.

• Implement proper locking mechanisms to prevent data corruption in concurrent access.

• Consider using optimistic concurrency control techniques to handle conflicts.

• Use database triggers or constraints to enforce data integrity rules.

• Regularly monitor and optimize database performance to prevent bottl...read more

Spring Boot controllers handle incoming HTTP requests and SQL commands are used to interact with databases.

• Spring Boot controllers are classes annotated with @RestController that handle incoming HTTP requests

• SQL commands are used to interact with databases to perform operations like insert, update, delete, and select

• Controllers in Spring Boot can use SQL commands to fetch data from a database and return it as a response to the client

ACID is a set of properties that guarantee reliable database transactions. Multi-threading involves multiple threads executing code concurrently.

• ACID stands for Atomicity, Consistency, Isolation, Durability

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

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

• Isolation ensures that transactions are executed independently without interference...read more

DML is used to manipulate data in a database, while DDL is used to define the structure of the database.

• DML stands for Data Manipulation Language and is used for operations like INSERT, UPDATE, DELETE.

• DDL stands for Data Definition Language and is used for operations like CREATE, ALTER, DROP.

• DML is used to modify existing data in a database, while DDL is used to define the structure of the database.

• Examples of DML statements: INSERT INTO table_name VALUES (value1, value2); UP...read more