AWS Database Specialty (DBS-C01) Interview Questions

Well, interview preparation for any exam is an essential step towards achieving the desired goal. Preparing for an interview like DBS-C01 makes it necessary to not only have expertise in the technical field but also the capability to demonstrate the answers well. In order to boost your preparation for the interview, our experts have compiled the set of very frequently asked and the best possible DBS-C01 interview questions. These will help you gain a fair idea about how the interview actually goes but before starting with the questions let’s take an overview of the exam.

The AWS Database Specialty certification exam is recommended for candidates who perform a database-focused role. This exam justifies your comprehensive understanding of databases, including the concepts of design, migration, deployment, access, maintenance, automation, monitoring, security, and troubleshooting. Further, it tests your ability to recommend, design, and maintain the optimal AWS database solution to improve performance, reduce costs, and enable innovation. Candidates who wish to give the exam must-

• Understand and differentiate the key features of AWS database services.
• Know how to analyze needs and requirements to recommend and design appropriate database solutions using AWS services

Let’s straightly move to the interview questions now.

Explain Amazon Database.

Amazon database offered by the Amazon Web Services(AWS) is a managed database along with managed service and NoSQL. Its service is maintained entirely via a controlled petabyte-scale data warehouse and in-memory caching. One or more AWS services, such as DynamoDB, RedShift, RDS, and ElastiCache, can be used by the user.

What does Amazon RDS stand for?

Amazon RDS stands for Amazon Relational Database

Name some Amazon RDS engines.

Some of the Amazon Relational Database engines are as follows:

• MySQL
• Amazon Aurora
• PostgreSQL
• SQL Server
• Oracle
• MariaDB

What do you mean by key-value store?

A key-value store is a basic database service that allows storing, querying and updating of the objects that are generally identified with the key and values. These objects are the keys and values that contain the actual data to be saved.

What does standby RDS instance do?

The primary goal of the standby RDS instance is to keep the infrastructure running (if it occurs). It’s kept in a separate availability zone with an entirely distinct infrastructure, both geographically and in terms of infrastructure.

What do you mean by Amazon ElastiCache?

Amazon ElastiCache is meant to improve the performance of web applications with the help of the caching of information which is used again and again. The information can be accessed at a very fast rate with the use of in-memory-caching. ElastiCache discards the need of managing a separate caching server. Hence, one can easily deploy or run an open-source compatible in-memory data source with high throughput and low latency.

Which database management services Amazon offers?

The database management services that Amazon offers are-DynamoDB, RedShift, ElastiCache and RDS.

What do you know about Data Warehouse?

A data warehouse is a repository where the data that is generated from a company’s systems and other sources is collected and stored. Moreover, a data warehouse has three-tier architecture:

• At the bottom, we have the tools which cleanse and collect the data.
• In the middle tier, we have tools that convert the data using Online Analytical Processing Server.
• At the top tier, we have different tools where data analysis and data mining are performed at the front end.

What do you mean by DynamoDB?

DynamoDB is a NoSQL database service that gives you the performance you need. DynamoDB is a supervisory database that also has a high level of scalability. Configuration, hardware provisioning, throughput capacity, setup, replication, software patching, and cluster scalability are all taken care of for users. As a result, it assists users in delegating scaling and running distributed databases to AWS.

Name the scalar data types supported by DynamoDB?

The scalar datatypes that DynamoDB supports are:

• Binary
• Boolean
• String
• Number

What are the benefits of auto-scaling?

Auto-scaling has the following benefits:

• Better availability
• Good cost management
• Better fault tolerance

How does data loads in Amazon Redshift?

Well, Amazon DynamoDB, Amazon EMR, AWS Data Pipeline, AWS Glue are some of the data sources that help in loading data in the RedShift data warehouse. Also, the clients with the help of ODBC or JDBC can connect to Redshift and give the SQL command of ‘insert’ to load the data.

What does VPC stand for?

VPC stands for Virtual Private Cloud. 

What is the use of VPC?

A VPC is one of the best ways to connect to cloud resources from one’s own data center. Once you connect your data center to the VPC in which your instances are present, each instance gets a private IP address that can access from your data center. As a result, you may access resources in the public cloud as if they were on your own private network.

How would you describe Database Management System?

A Database Management System(DBMS) is the application that handles the heavy lifting between the user and the raw data. The database cannot alter its own data anymore than the average person can re-arrange their genetic code. When you are asking questions, it is the DBMS that you are talking to. It is what looks at your question, thinks about it, goes to the database, picks up the data, hands it back to you, and then asks you to come again.

What is Replication?

Database replication facilitates real-time automated backups between multiple database servers. In case the main server goes down, this allows the creation of either a fall-over server or warm back up for use.

What is a Hadoop application?

The HDFS Hadoop application locates the document framework where Hadoop data get stored. It has a dynamic document structure with a large data transmission capability.

What is Amazon EC2?

Amazon EC2 is a cloud computing service that offers resizable compute power. Its architecture makes software developers’ lives easier when it comes to web-scale cloud computing. The service interface for Amazon EC2 allows developers to get and thus configure capacity with little effort.

What are the different components of Hadoop?

Hadoop comprises of the following components: 

1. HDFS 
2. MapReduce 
3. Hadoop Common 
4. YARN 

What do you mean by Cloud Computing?

Cloud Computing is a usual catch-all term for data that is stored over there. Placing high-requirement applications onto dedicated hosting services can be both beneficial and catastrophic in terms of security problems and availability issues. Therefore, it is highly recommended to keep the important data in-house, and only outsource in situations that can’t be avoided. Cloud Computing and Big Data are talked about in the same sentence as the processing power required for one usually mean the others become viable either as a requirement or a side effect.

Mention the different deployment models?

The different deployment models are:

• Private Cloud
• Hybrid Clouds
• Public Cloud

What is the process of migration in AWS?

The three-phase process of migration helps an organization approach a migration of tens, hundreds, or thousands of applications. This is an iterative process, not a series of distinct steps. You’ll be able to drive repeatability and predictability in procedures as you iterate additional apps, and you’ll see that the migration process is speeding up.

Mention the features of AWS database.

Some common features of Amazon database are:

• Easy administration
• More secure
• High scalablity
• Reliable
• Faster performance
• High availability
• Durable
• Cost-effective

What are the benefits of Amazon Redshift?

Well, some of the prominent advantages of Amazon Redshift are-

1. Very easy to use- In the AWS RedShift console, you will see the option of creating a cluster. All you need to do is to click on that and leave the rest on the machine programming of RedShift. After launching, the cluster gets ready to use as RedShift automates most of the tasks like managing, monitoring, and scaling.
2. Better and fast performance- It uses specific strategies like columnar storage and massively parallels processing strategies so as to provide high throughput and response time.
3. Economical- It does not require any setup so the cost automatically reduces in comparison to the traditional data warehouse.
4. Easy scaling of the warehouse- You only need to resize the cluster size by increasing the number of compute nodes.

What type of engines does Elasticache use?

Elasticache supports a two type engine: Memcached and Redis.

What does AMI mean?

Amazon Machine Image(AMI) is a template that provides the information for launching an instance, that is actually a copy of the AMI running as a virtual server in the cloud. As a result, you may run instances from as many distinct AMIs as you like.

What do you mean by Leader Node?

The work of the leader node is to receive queries from the client application, parse them, and hence develop the execution plan. It then creates stages to process these queries before returning the results to the client application.

Name the collection data types supported by DynamoDB?

The collection datatypes that DynamoDB supports are:

• Binary Set
• Number Set
• Heterogeneous Map
• String Set
• Heterogeneous List

Explain Memcached.

Memcached is a popular in-memory data store that developers use for the high-performance cache to speed up the applications. Memcached can retrieve the data in less than a millisecond by storing the data in memory instead of disk. It works by storing every value of the key for every other piece of data, uniquely identifying each piece of information, and allowing Memcached to easily locate the record.