Altrad Group Interview Questions and Answers

End to end project architecture involves designing and implementing a data pipeline to process and analyze data from various sources.

• Define project requirements and goals

• Design data architecture including data sources, storage, processing, and analytics tools

• Implement data pipeline to extract, transform, and load data

• Ensure data quality and consistency throughout the pipeline

• Monitor and optimize performance of the data pipeline

• Examples: Using Apache Kafka for real-time data s...read more

Using Common Table Expressions (CTEs) to delete duplicates in SQL query

• Use a CTE to identify duplicates by ranking rows based on a unique identifier

• Delete rows with duplicate ranks in the main query

SQL joins combine data from two or more tables based on a related column between them.

• Different types of SQL joins include INNER JOIN, LEFT JOIN, RIGHT JOIN, and FULL JOIN.

• The number of records in the result of a join depends on the type of join and the data in the tables.

• For example, an INNER JOIN will only return records that have matching values in both tables, while a LEFT JOIN will return all records from the left table and matching records from the right table.

Implemented query optimization techniques to improve performance in data processing.

• Utilized indexing to speed up data retrieval

• Optimized SQL queries by rewriting them for better performance

• Implemented caching mechanisms to reduce redundant data processing

Reverse a list without using inbuilt functions

• Create two pointers, one at the start and one at the end of the array

• Swap the elements at the two pointers and move them towards the center until they meet

• Repeat the process until the entire list is reversed