AWS Certified Developer Associate 6: Multiple Choice
Questions And Correct Answers with Rationale,100%
Verified
You are a developer for a company that is planning on using the AWS RDS
service. Your Database administrator spins up a new MySQL RDS Instance in
AWS. You now need to connect to that instance. How can you achieve this?
Choose 2 answers from the options given below.
A. Use the DescribeDBInstances API and get the endpoint for the database
instance
B. Use the DescribeDBInstances API and get the IP address for the database
instance
C Request the DBA for the endpoint for the Instance via the AWS Console
D. Request the DBA for the IP address for the Instance via the AWS Console
Answer - A and C
The AWS Documentation mentions the following
Before you can connect to a DB instance running the MySQL database engine, you
must create a DB instance. For
information, seeCreating a DB Instance Running the MySQL Database Engine. Once
Amazon RDS provisions your
DB instance, you can use any standard MySQL client application or utility to connect to
the instance. In the
connection string, you specify the DNS address from the DB instance endpoint as the
host parameter and
specify the port number from the DB instance endpoint as the port parameter.
You can use the AWS Management Console, the AWS CLI describe-db-instances
command, or the Amazon RDS
API DescribeDBInstances action to list the details of an Amazon RDS DB instance,
including its endpoint
Options B and D are incorrect since you need to use the endpoints to connect to the
database
For more information on connecting to a database endpoint , please refer to the below
URL
https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_ConnectToInstanc
e.html
You are a developer for a company that has been given the responsibility to
debug
performance issues for an existing application. The application connects to a
MySQL RDS Instance in AWS. There is a suspicion that there are performance
issues in the underlying queries. Which of the following can help diagnose these
issues?
A. The Cloudtrail logs for the region
B. Get the slow query logs for the RDS service
,C. Use the AWS Config service to diagnose the problem areas
D. Use the AWS Inspector service to diagnose the problem areas
Answer - B
The AWS RDS Service contains several logs such as the ones given below
Error log (https://dev.mysql.com/doc/refman/5.7/en/error-log.html) - contains diagnostic
messages generated by the database engine, along with startup and shutdown times.
General query log (https://dev.mysql.com/doc/refman/5.7/en/query-log.html) - contains a
record of all
SQL statements received from clients, and also client connect and disconnect times.
Slow query log (https://dev.mysql.com/doc/refman/5.7/en/slow-query-log.html) -
contains a record of
SQL statements that took longer to execute than a set amount of time and that
examined more than a
defined number of rows. Both thresholds are configurable.
Option A is incorrect because this is used to monitor API activity
Option C is incorrect because this is used as a configuration service
Option D is incorrect because this is used to inspect EC2 Instances for vulnerabilities
For more information on monitoring Amazon RDS , please refer to the below URL
https://aws.amazon.com/blogs/database/monitor-amazon-rds-for-mysql-and-mariadb-
logs-withamazon-
cloudwatch/
Your team has an application deployed using the Elastic Beanstalk service. A
Web
environment has been configured for the production environment. There is now a
requirement to perform a Blue Green deployment for a new version of the
application. How
can you achieve this?
A. Create a new application and swap the application environments.
B. Create a new application version and upload the new application version
C. Create a new environment in the application with the updated application
version and perform
a swap
D. Create a new environment in the application and Load the configuration of an
existing
environment
Answer - C
This is mentioned in the AWS Documentation
Since this is clearly mentioned in the AWS Documentation, all other options are invalid
For more information on Blue Green deployments in Elastic Beanstalk, please refer to
the below URL
https://docs.aws.amazon.com/elasticbeanstalk/latest/dg/using-
features.CNAMESwap.html
You are developing an application that consist of the following architecture
· A set of EC2 Instances hosting a web layer
,· A database hosting a MySQL instance
You need to add a layer that can be used to ensure that the most frequently
accessed data
from the database is fetched in a more fast and efficient manner from the
database. Which
of the following can be used to accomplish this requirement?
A. An SQS queue to store the frequently accessed data
B. An SNS topic to store the frequently accessed data
C. A Cloudfront distribution to store the frequently accessed data
D. A Elasticache instance to store the frequently accessed data
Answer - D
The AWS Documentation mentions the following
Amazon ElastiCache offers fully managed Redis (https://aws.amazon.com/redis/) and
Memcached
(https://aws.amazon.com/memcached/). Seamlessly deploy, run, and scale popular
open source compatible inmemory
data stores. Build data-intensive apps or improve the performance of your existing apps
by retrieving
data from high throughput and low latency in-memory data stores. Amazon ElastiCache
is a popular choice for
Gaming, Ad-Tech, Financial Services, Healthcare, and IoT apps.
Option A is incorrect because this is a messaging service
Option B is incorrect because this is a notification service
Option C is incorrect because this is a web distribution service
For more information on Amazon ElastiCache, please refer to the below URL
You've just started development on an application that will make use of the
ElastiCache
service. You need to ensure that objects are cached but not kept inadvertently for
a long
time. Which of the following cache maintenance strategy would you employ for
the cache
service?
A. TTL
B. Lazy Loading
C. Write Through
D. Read Through
Answer - A
The AWS Documentation mentions the following
Lazy loading allows for stale data but won't fail with empty nodes. Write through ensures
that data is always fresh
but may fail with empty nodes and may populate the cache with superfluous data. By
adding a time to live (TTL) value to each write, we are able to enjoy the advantages of
each strategy and largely avoid cluttering up the cache
with superfluous data.
, Option B is incorrect because this is a caching strategy that loads data into the cache
only when necessary.
Option C is incorrect because this is a caching strategy that adds data or updates data
in the cache whenever
data is written to the database.
Option D is incorrect because there is no such caching strategy
For more information on Caching strategies, please refer to the below URL
https://docs.aws.amazon.com/AmazonElastiCache/latest/red-ug/Strategies.html
Your team has been instructed with the development of an application. The
backend store
needs to store data on which ad-hoc queries can run and table joins are required.
Which of
the following would you use to host the underlying data store?
A. AWS RDS
B. AWS DynamoDB
C. AWS S3
D. AWS Athena
Answer - A
The AWS Documentation gives an example comparison of when to use AWS RDS for
SQL data and DynamoDB for NoSQL data
Option B is incorrect because this should not be used when you have table joins to be
carried out.
Option C is incorrect because this is used for object level storage
Option D is incorrect because this is used for querying data in S3
For more information on when to use SQL over NoSQL, please refer to the below URL
https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/SQLtoNoSQL.ht
ml
Your development team is currently working with an application that interacts
with the
DynamoDB table. Due to the proposed extensive use of the application, the
underlying
DynamoDB table would undergo a steady growth in size. Which of the following
preferred
options should be used for retrieving the data? Choose 3 answers from the
options given
below
A. Use the query operation
B. Use the Scan operation
C. Use the GetItem API command
D. Use the BatchGetItem API command
Answer - A ,C and D
The AWS Documentation mentions the following
If possible, you should avoid using a Scan operation on a large table or index with a
filter that removes many
Questions And Correct Answers with Rationale,100%
Verified
You are a developer for a company that is planning on using the AWS RDS
service. Your Database administrator spins up a new MySQL RDS Instance in
AWS. You now need to connect to that instance. How can you achieve this?
Choose 2 answers from the options given below.
A. Use the DescribeDBInstances API and get the endpoint for the database
instance
B. Use the DescribeDBInstances API and get the IP address for the database
instance
C Request the DBA for the endpoint for the Instance via the AWS Console
D. Request the DBA for the IP address for the Instance via the AWS Console
Answer - A and C
The AWS Documentation mentions the following
Before you can connect to a DB instance running the MySQL database engine, you
must create a DB instance. For
information, seeCreating a DB Instance Running the MySQL Database Engine. Once
Amazon RDS provisions your
DB instance, you can use any standard MySQL client application or utility to connect to
the instance. In the
connection string, you specify the DNS address from the DB instance endpoint as the
host parameter and
specify the port number from the DB instance endpoint as the port parameter.
You can use the AWS Management Console, the AWS CLI describe-db-instances
command, or the Amazon RDS
API DescribeDBInstances action to list the details of an Amazon RDS DB instance,
including its endpoint
Options B and D are incorrect since you need to use the endpoints to connect to the
database
For more information on connecting to a database endpoint , please refer to the below
URL
https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_ConnectToInstanc
e.html
You are a developer for a company that has been given the responsibility to
debug
performance issues for an existing application. The application connects to a
MySQL RDS Instance in AWS. There is a suspicion that there are performance
issues in the underlying queries. Which of the following can help diagnose these
issues?
A. The Cloudtrail logs for the region
B. Get the slow query logs for the RDS service
,C. Use the AWS Config service to diagnose the problem areas
D. Use the AWS Inspector service to diagnose the problem areas
Answer - B
The AWS RDS Service contains several logs such as the ones given below
Error log (https://dev.mysql.com/doc/refman/5.7/en/error-log.html) - contains diagnostic
messages generated by the database engine, along with startup and shutdown times.
General query log (https://dev.mysql.com/doc/refman/5.7/en/query-log.html) - contains a
record of all
SQL statements received from clients, and also client connect and disconnect times.
Slow query log (https://dev.mysql.com/doc/refman/5.7/en/slow-query-log.html) -
contains a record of
SQL statements that took longer to execute than a set amount of time and that
examined more than a
defined number of rows. Both thresholds are configurable.
Option A is incorrect because this is used to monitor API activity
Option C is incorrect because this is used as a configuration service
Option D is incorrect because this is used to inspect EC2 Instances for vulnerabilities
For more information on monitoring Amazon RDS , please refer to the below URL
https://aws.amazon.com/blogs/database/monitor-amazon-rds-for-mysql-and-mariadb-
logs-withamazon-
cloudwatch/
Your team has an application deployed using the Elastic Beanstalk service. A
Web
environment has been configured for the production environment. There is now a
requirement to perform a Blue Green deployment for a new version of the
application. How
can you achieve this?
A. Create a new application and swap the application environments.
B. Create a new application version and upload the new application version
C. Create a new environment in the application with the updated application
version and perform
a swap
D. Create a new environment in the application and Load the configuration of an
existing
environment
Answer - C
This is mentioned in the AWS Documentation
Since this is clearly mentioned in the AWS Documentation, all other options are invalid
For more information on Blue Green deployments in Elastic Beanstalk, please refer to
the below URL
https://docs.aws.amazon.com/elasticbeanstalk/latest/dg/using-
features.CNAMESwap.html
You are developing an application that consist of the following architecture
· A set of EC2 Instances hosting a web layer
,· A database hosting a MySQL instance
You need to add a layer that can be used to ensure that the most frequently
accessed data
from the database is fetched in a more fast and efficient manner from the
database. Which
of the following can be used to accomplish this requirement?
A. An SQS queue to store the frequently accessed data
B. An SNS topic to store the frequently accessed data
C. A Cloudfront distribution to store the frequently accessed data
D. A Elasticache instance to store the frequently accessed data
Answer - D
The AWS Documentation mentions the following
Amazon ElastiCache offers fully managed Redis (https://aws.amazon.com/redis/) and
Memcached
(https://aws.amazon.com/memcached/). Seamlessly deploy, run, and scale popular
open source compatible inmemory
data stores. Build data-intensive apps or improve the performance of your existing apps
by retrieving
data from high throughput and low latency in-memory data stores. Amazon ElastiCache
is a popular choice for
Gaming, Ad-Tech, Financial Services, Healthcare, and IoT apps.
Option A is incorrect because this is a messaging service
Option B is incorrect because this is a notification service
Option C is incorrect because this is a web distribution service
For more information on Amazon ElastiCache, please refer to the below URL
You've just started development on an application that will make use of the
ElastiCache
service. You need to ensure that objects are cached but not kept inadvertently for
a long
time. Which of the following cache maintenance strategy would you employ for
the cache
service?
A. TTL
B. Lazy Loading
C. Write Through
D. Read Through
Answer - A
The AWS Documentation mentions the following
Lazy loading allows for stale data but won't fail with empty nodes. Write through ensures
that data is always fresh
but may fail with empty nodes and may populate the cache with superfluous data. By
adding a time to live (TTL) value to each write, we are able to enjoy the advantages of
each strategy and largely avoid cluttering up the cache
with superfluous data.
, Option B is incorrect because this is a caching strategy that loads data into the cache
only when necessary.
Option C is incorrect because this is a caching strategy that adds data or updates data
in the cache whenever
data is written to the database.
Option D is incorrect because there is no such caching strategy
For more information on Caching strategies, please refer to the below URL
https://docs.aws.amazon.com/AmazonElastiCache/latest/red-ug/Strategies.html
Your team has been instructed with the development of an application. The
backend store
needs to store data on which ad-hoc queries can run and table joins are required.
Which of
the following would you use to host the underlying data store?
A. AWS RDS
B. AWS DynamoDB
C. AWS S3
D. AWS Athena
Answer - A
The AWS Documentation gives an example comparison of when to use AWS RDS for
SQL data and DynamoDB for NoSQL data
Option B is incorrect because this should not be used when you have table joins to be
carried out.
Option C is incorrect because this is used for object level storage
Option D is incorrect because this is used for querying data in S3
For more information on when to use SQL over NoSQL, please refer to the below URL
https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/SQLtoNoSQL.ht
ml
Your development team is currently working with an application that interacts
with the
DynamoDB table. Due to the proposed extensive use of the application, the
underlying
DynamoDB table would undergo a steady growth in size. Which of the following
preferred
options should be used for retrieving the data? Choose 3 answers from the
options given
below
A. Use the query operation
B. Use the Scan operation
C. Use the GetItem API command
D. Use the BatchGetItem API command
Answer - A ,C and D
The AWS Documentation mentions the following
If possible, you should avoid using a Scan operation on a large table or index with a
filter that removes many
