Koch Business Solutions Data Engineer Interview Questions and Answers

Rank assigns unique ranks to rows, while dense_rank handles ties by assigning the same rank to tied rows. Left join includes all rows from the left table and matching rows from the right table, while left anti join includes only rows from the left table that do not have a match in the right table.

• Rank assigns unique ranks to rows based on the specified order, while dense_rank handles ties by assigning the same rank to ...read more

I have experience working on projects involving data pipeline development, ETL processes, and data warehousing.

• Developed ETL processes to extract, transform, and load data from various sources into a data warehouse

• Built data pipelines to automate the flow of data between systems and ensure data quality and consistency

• Optimized database performance and implemented data modeling best practices

• Worked on real-time data pro...read more

A palindrome is a word, phrase, number, or other sequence of characters that reads the same forward and backward.

• Check if the string is equal to its reverse to determine if it's a palindrome.

• Ignore spaces and punctuation when checking for palindromes.

• Convert the string to lowercase before checking for palindromes.

• Examples: 'racecar', 'A man, a plan, a canal, Panama'

Pods are the smallest deployable units in Kubernetes, consisting of one or more containers.

• Pods are used to run and manage containers in Kubernetes

• Each pod has its own unique IP address within the Kubernetes cluster

• Pods can contain multiple containers that share resources and are scheduled together

• Pods are ephemeral and can be easily created, destroyed, or replicated

• Pods can be managed and scaled using Kubernetes contr

To create a DBT project, you need to set up a project directory, create models, define sources, and run tests.

• Set up a project directory with a dbt_project.yml file

• Create models in the models directory using SQL files

• Define sources in the sources.yml file

• Run tests using dbt test command

Materializations in dbt are pre-computed tables that store the results of dbt models for faster query performance.

• Materializations are created using the 'materialized' parameter in dbt models.

• Common types of materializations include 'view', 'table', and 'incremental'.

• Materializations help improve query performance by reducing the need to recompute data on every query.

• Materializations can be refreshed manually or automa

dbt snapshots are a way to capture the state of your data model at a specific point in time.

• dbt snapshots are used to create point-in-time snapshots of your data model

• They allow you to track changes in your data over time

• Snapshots can be used for auditing, debugging, or creating historical reports

Window functions in SQL are used to perform calculations across a set of table rows related to the current row.

• Window functions are used to calculate values based on a specific subset of rows within a table.

• They allow for ranking, aggregation, and other calculations without grouping the rows.

• Examples of window functions include ROW_NUMBER(), RANK(), and SUM() OVER().

Delta Lake is an open-source storage layer that brings ACID transactions to Apache Spark and big data workloads.

• Delta Lake is built on top of Apache Spark and provides ACID transactions for big data processing.

• It allows for schema enforcement and evolution, data versioning, and time travel queries.

• Delta Lake is compatible with popular data science and machine learning libraries like TensorFlow and PyTorch.