20+ Baroda Steel And Metal Corporation Interview Questions and Answers

Query to get the customer with the highest total order value for each year, month.

• Join the Order and Customer tables on the foreign key

• Group the results by year, month, and customer

• Calculate the total order value for each group

• Find the maximum total order value for each year, month

• If there are multiple customers with the same highest total order value, select the one with the lower Customer_ID

To fetch the modified information without ModifiedDate column from a table with 10 million records.

• Create a trigger to capture the modified information and insert it into a separate table with ModifiedDate column.

• Use a tool like Change Data Capture (CDC) to track changes in the table and extract the modified information.

• Use a query to compare the current table with a backup copy taken the previous day to identify the modified information.

Handle changing schema by using schema evolution techniques and version control.

• Use schema evolution techniques like adding new fields, renaming fields, and changing data types.

• Implement version control to track changes and ensure backward compatibility.

• Use tools like Apache Avro or Apache Parquet to store data in a self-describing format.

• Implement automated testing to ensure data quality and consistency.

• Collaborate with data producers to establish clear communication and doc...read more

Normalisation is the process of organizing data in a database to reduce redundancy and improve data integrity. Denormalisation is the opposite process.

• Normalisation is used to eliminate data redundancy and improve data integrity.

• Denormalisation is used to improve query performance by reducing the number of joins required.

• A real-time example of normalisation is breaking down a customer's information into separate tables such as customer details, order details, and payment deta...read more

Parquet and ORC are columnar storage formats. Parquet is preferred due to its cross-platform support and better compression. ORC supports schema evolution.

• Parquet is a columnar storage format that is widely used in the industry due to its cross-platform support and better compression.

• ORC is another columnar storage format that supports schema evolution.

• Parquet is preferred over ORC due to its better compression and support for a wider range of programming languages.

• ORC is pre...read more

There are three types of schema in Data Warehousing: Star Schema, Snowflake Schema, and Fact Constellation Schema.

• Star Schema: central fact table connected to dimension tables in a star shape

• Snowflake Schema: extension of star schema with normalized dimension tables

• Fact Constellation Schema: multiple fact tables connected to dimension tables in a complex structure

Broadcast variables are read-only variables that are cached on each worker node while accumulator variables are write-only variables that are used to accumulate values across multiple tasks.

• Broadcast variables are used to give every node a copy of a large input dataset or a small lookup table.

• Accumulator variables are used to keep a running total of values across multiple tasks.

• Broadcast variables are used for read-only operations while accumulator variables are used for writ...read more

Design a system for sequential transactions with rollback on failure

• Use a transaction manager to coordinate the two transactions

• Implement a try-catch mechanism to handle failures and trigger rollback if needed

• Ensure that both transactions are part of the same unit of work

SCD (Slowly Changing Dimensions) types are used to track changes in data over time.

• Type 1: Overwrite the old data with new data

• Type 2: Create a new record with a new primary key

• Type 3: Create a new column to store the old data

• Type 4: Create a separate table to store the old data

• Type 6: Hybrid of Type 1 and Type 2

Implement timer in React using useTimeout and disable it after unmounting

• Use useState to store the timer ID

• Use useEffect to start the timer on component mount and clear it on unmount

• Use clearTimeout to disable the timer when the component unmounts

To handle hashmap memory leak, ensure proper management of keys and values, use weak references, and periodically check for unused entries.

• Avoid storing unnecessary data in the hashmap

• Use weak references for keys or values if appropriate

• Periodically check for and remove unused entries to free up memory

Kafka is a distributed streaming platform, Partition is a way to divide data, ConsumerGroup is a group of consumers sharing the load.

• Kafka is a distributed streaming platform used for building real-time data pipelines and streaming applications.

• Partition is a way to divide data within a Kafka topic to allow for parallel processing and scalability.

• ConsumerGroup is a group of consumers that work together to consume data from Kafka topics, each consumer within the group reads fr...read more

Yes, I am comfortable with WFO (Work From Office) as it is the primary mode of work.

• I have experience working in a WFO environment in my previous roles.

• I am familiar with the expectations and responsibilities of working in an office setting.

• I am adaptable and can easily transition between WFO and WFH (Work From Home) as needed.

Nested queries are used to retrieve data from multiple tables in a database.

• Use subqueries to retrieve data from a nested query within the main query.

• Use JOIN statements to combine data from multiple tables in a nested query.

• Nested queries can be used in SELECT, INSERT, UPDATE, and DELETE statements.

Normalization is the process of organizing data in a database to reduce redundancy and improve data integrity.

• Normalization involves breaking down a database into smaller, more manageable tables.

• It helps in reducing data redundancy by storing data in a structured manner.

• Normalization ensures data integrity by minimizing the chances of anomalies during data manipulation.

• There are different levels of normalization such as 1NF, 2NF, 3NF, and BCNF.

• Example: In a database of studen...read more

Exception handling is a programming concept that deals with errors during program execution.

• Exception handling allows for graceful handling of errors in a program.

• It involves try, catch, and finally blocks to handle exceptions.

• Examples include catching divide by zero errors or file not found exceptions.

BPO stands for Business Process Outsourcing, where a company contracts out specific business tasks to a third-party service provider.

• BPO companies handle tasks such as customer service, technical support, data entry, and more for other businesses.

• Companies outsource these tasks to BPOs to save costs, improve efficiency, and focus on core business functions.

• BPOs may operate onshore, nearshore, or offshore, depending on the location of the service provider.

• Examples of BPO compa...read more

Handle customers with patience, empathy, and excellent communication skills.

• Listen actively to the customer's concerns and needs

• Show empathy and understanding towards their situation

• Communicate clearly and effectively to address their issues

• Offer solutions and assistance to resolve any problems

• Follow up to ensure customer satisfaction

Streams in Node.JS allow for efficient handling of data by reading or writing it in chunks rather than all at once.

• Streams are instances of EventEmitter class in Node.JS

• There are four types of streams in Node.JS: Readable, Writable, Duplex, and Transform

• Streams can be used for reading files, handling HTTP requests, and processing large amounts of data efficiently

The gold rules of accounts are basic principles that guide the recording of financial transactions.

• The golden rules of accounts are: Debit what comes in, Credit what goes out; Debit the receiver, Credit the giver; Debit expenses and losses, Credit income and gains.

• For example, when cash is received, it is debited as it is coming in. When cash is paid out, it is credited as it is going out.

• Similarly, when goods are purchased on credit, the receiver (goods) is debited and when ...read more