Redshift interview question

Redshift interview question [2022]

For those preparing for the redshift interview, I will shortly drop 12 redshift interview questions to help in your preparation. 

Redshift is a cloud-based platform that runs on Amazon Web Services, the Company’s current cloud infrastructure. One of the most significant advantages is that Redshift is a scalable architecture that can adapt to changing storage demands in seconds. Scaling can be costly and complex, a crucial concern for enterprises with rapidly changing data requirements.


Common redshift interview questions and answer 


  • What is the aim of using the Amazon Web Services Redshift database?

Amazon Redshift is a cloud-based, managed petabyte-size data warehouse solution. You could startup with a few gigabytes of data and scale to a petabyte or more.

It’s used to leverage our data to gain fresh insights for our Company and customers.


  • What is Amazon Redshift’s AQUA?

Redshift’s Advanced Query Accelerator (AQUA) is a hardware-accelerated cache that allows it to run up to 10 times quicker than any other enterprise cloud data warehouse.

Data must be transported to computing clusters for processing in a warehousing architecture with centralized storage.

AQUA brings computation to storage by doing a large portion of data processing on the innovative cache.


  • What are the essential features of Redshift?

Operations : Similar to RDS, Security : IAM,KMS ,VPC,SSL(similar to RDS)

Redshift provides 10times more performance compared to other warehouse services. Redshift is highly available and has an auto-healing feature.

Redshift provides pay per node provisioned, 1/10th of the cost compared to other data warehouse services.

  • Is Redshift the same as RDS?

Redshift is a substantially modified version of PostgreSQL that isn’t used for OLTP.

Remember that OLTP stands for online transaction processing.

As a result, Redshift is not a substitute for RDS.OLAP stands for online analytical processing, and Redshift is OLAP. For example, Redshift is utilized for data warehousing and analytics.

What exactly is MPP? Does Redshift support MPP?

MPP (Massively Parallel Query Execution) is the acronym for massively parallel query execution?

It’s highly distributed; when you execute a query, it’ll operate in parallel over many instances and cores.

As a result, this is a massively parallel query execution, which makes the database very available.


  • What are the different types of nodes supported by Redshift, and what are their functions?


Redshift has two nodes: a leader node and a compute node. There is a leader node, which is responsible for query planning and aggregation across all compute nodes. So the computing nodes will execute the queries and report the results back to the leader. If you only have one node, it serves as both a leader and a computing node.


  • How does Redshift stack up against competing for data warehouse solutions in terms of performance?

Redshift outperforms competing for data warehouse systems tenfold, and it’s designed to scale up to 2 petabytes of data. Petabytes (1 petabyte = 1000 terabytes) denote a large amount of data.

  • What are the best scenarios for employing the Classic and Application Load Balancers?


For simple traffic load balancing across multiple EC2 instances, the Classic Load Balancer is the best option.

The Application LoadBalancer, on the other hand, is appropriate for container-based or microservices architectures in which traffic must be routed to separate services, or load balancing must be performed across many ports on the same EC2 instance.


How do you keep your Redshift cluster’s costs low?

Costs for your Redshift cluster can be reduced in a variety of ways, including the following:

Reservations for nodes


Encoding and compression of columns should be done correctly.

When not in use, the Redshift cluster is paused, and it is resumed when needed.

Ensure that vacuum is operating and that disk space is being reclaimed.

  • What issues did you run into while using Amazon Redshift?
  • The majority of consumers deal with inquiries that are extremely slow and take a long time to respond to.
  • Another issue appears to be on the dashboard. The dashboard is unacceptably slow.
  • “Black box” is another issue with Amazon Redshift. Observing ‘what’s happening on’ is tricky.


  • On Redshift, how do we run SQL files?

To set up a JDBC connection to Redshift, you can run a simple Python script on an EC2 instance. Execute the queries after it’s finished—a database in SQL.

  • Your development team wants to use the production Redshift cluster to test their new enhancement code. What is the best course of action? Do you think you’d let them into the production environment?

You can take a snapshot of the production Redshift cluster and use it to start a new development cluster. The development team can work on this cluster without affecting production.

  • What is an Amazon Redshift-controlled garage, and how does it work?

Amazon Redshift managed storage is available with RA3 node types, allowing you to grow to compute and storage one at a time, allowing you to construct your cluster primarily based on your computational requirements. It uses a high-overall performance SSD-based local garage as a Tier-1 cache. It takes advantage of optimizations such as statistics block temperature, statistics blockage, and workload styles to provide high overall performance while scaling the garage to Amazon S3 automatically as needed without requiring action.


To bring down the amount of I/O required to run queries, Redshift employs columnar storage, statistics compression, and sector mapping. It parallelizes and distributes SQL operations using a massively parallel processing statistics warehouse framework. Redshift uses system learning to provide high throughput based on your workloads. For recurrent queries, Redshift uses result caching to provide sub-2nd reaction instances. Redshift backs up your statistics to S3 regularly. It can asynchronously mirror your snapshots to S3 in multiple locations for disaster recovery.

Final thought 

Your excellent performance in the interview does not guarantee you will get the job. You will do a drug test for all its candidates. Redshift workers must be committed to maintaining a drug-free work environment. As a Company employee, you must obey all Company regulations regarding alcohol abuse and the ownership, sale, and use of illegal substances.