DBS-C01 Deployment and Migration Practice Test 18 — 15 Questions

Question 1

A company is migrating a 2 TB Oracle database to Amazon Aurora PostgreSQL using AWS SCT and DMS. After migration, the application reports that some queries are significantly slower than before. The database schema was converted automatically. What is the most likely cause?

Accepted Answer

The schema conversion did not create appropriate indexes. Option C is correct because SCT may not always generate optimal indexes for Aurora PostgreSQL, leading to performance issues. Option A is wrong because Aurora PostgreSQL supports partitioning. Option B is wrong because DMS does not affect query execution plans. Option D is wrong because storage performance should not cause query slowness.

Answer

Aurora storage is slower than Oracle's storage

Answer

DMS introduced data type conversions that slow down queries

Answer

Aurora PostgreSQL does not support partitioning, causing full table scans

Question 2

A company is migrating a 500 GB database from Amazon RDS for MySQL to Amazon Aurora MySQL. The migration must be completed with minimal downtime and no data loss. The RDS instance is Multi-AZ. Which approach should be used?

Accepted Answer

Create an Aurora MySQL read replica from the RDS MySQL instance, then promote it. Option A is correct because creating an Aurora read replica from the RDS MySQL instance allows for a nearly zero-downtime promotion. Option B is wrong because a snapshot restore is offline. Option C is wrong because DMS would introduce additional complexity and potential data loss. Option D is wrong because replication from a Multi-AZ standby is not supported.

Answer

Use AWS DMS with ongoing replication from RDS to Aurora

Answer

Take a snapshot of the RDS instance and restore to Aurora

Answer

Set up native MySQL replication from the RDS Multi-AZ standby to Aurora

Question 3

A company is migrating an on-premises Oracle database to Amazon RDS for Oracle. They need to minimize downtime. Which TWO actions should they take?

Accepted Answer

Set up AWS DMS with change data capture (CDC) from the source. Options A and C are correct. Setting up AWS DMS with ongoing replication allows minimal downtime, and validating the schema with SCT before migration is a best practice. Option B is wrong because disabling archiving would prevent CDC. Option D is wrong because increasing storage does not affect downtime. Option E is wrong because a single-AZ deployment does not inherently reduce downtime.

Answer

Increase the allocated storage on the target RDS instance to improve performance

Answer

Deploy the target RDS instance as a Single-AZ to simplify replication

Answer

Disable Oracle archivelog mode to speed up data transfer

Question 4

A company is migrating a 3 TB PostgreSQL database to Amazon Aurora PostgreSQL. The migration must have minimal downtime. Which THREE steps should be taken?

Accepted Answer

Use AWS DMS with ongoing replication from the source PostgreSQL database. Options A, C, and D are correct. Using DMS with CDC allows minimal downtime, Aurora supports read replicas for scaling, and adjusting instance class ensures performance. Option B is wrong because Snowball is for offline transfer. Option E is wrong because disabling autovacuum is not recommended and can lead to bloat.

Answer

Disable autovacuum on the Aurora cluster to improve migration performance

Answer

Use AWS Snowball Edge to transfer the data offline

Question 5

A company is planning to migrate a 1 TB SQL Server database to Amazon RDS for SQL Server. Which TWO factors should be considered when choosing the migration approach?

Accepted Answer

The need to modify the database schema for compatibility. Options A and C are correct. The acceptable downtime window determines whether offline or online migration is used, and the ability to modify the schema may require SCT. Option B is wrong because SQL Server Agent jobs can be migrated. Option D is wrong because the source SQL Server version affects compatibility. Option E is wrong because the number of concurrent users is not a primary factor.

Answer

The number of concurrent users accessing the database

Answer

Whether the database uses SQL Server Agent jobs

Answer

The version of the source SQL Server instance

Question 6

A company is migrating an on-premises PostgreSQL database to Amazon RDS for PostgreSQL. The database is 2 TB and has a sustained write rate of 150 MB/s. The migration must have minimal downtime. Which AWS service or tool should be used for the initial data load and ongoing replication?

Accepted Answer

Use AWS Database Migration Service (AWS DMS) with full load and ongoing replication. AWS DMS supports ongoing replication from on-premises to RDS with minimal downtime. Option A is incorrect because pg_dump/pg_restore cannot perform ongoing replication. Option B is incorrect because S3 is for storage, not database replication. Option D is incorrect because the Schema Conversion Tool does not handle data migration.

Answer

Use pg_dump and pg_restore

Answer

Use AWS Schema Conversion Tool (AWS SCT) to convert schema and AWS DMS for data migration

Answer

Use AWS S3 Transfer Acceleration to upload data to Amazon S3, then restore to RDS

Question 7

A company is deploying a new multi-AZ application that requires a relational database. The database must be highly available and must automatically failover to a standby in another Availability Zone within minutes. The database size is 500 GB and the workload is read-heavy. Which AWS RDS configuration meets these requirements?

Accepted Answer

Deploy Amazon RDS for MySQL with Multi-AZ and a read replica in a different AZ. Amazon RDS Multi-AZ deployment provides automatic failover to a standby in another AZ. Option B is incorrect because Multi-AZ is not available for Aurora; Aurora uses a cluster with a primary and readers. Option C is incorrect because cross-Region replicas are for disaster recovery, not automatic failover in the same Region. Option D is incorrect because RDS Proxy is for connection pooling, not high availability.

Answer

Deploy Amazon Aurora with Multi-AZ

Answer

Deploy Amazon RDS for PostgreSQL with a cross-Region read replica

Answer

Deploy Amazon RDS for Oracle with RDS Proxy

Question 8

A developer is deploying an application that uses Amazon DynamoDB as its database. The application experiences sudden spikes in traffic. Which DynamoDB feature should the developer use to handle the spikes without manual intervention?

Accepted Answer

DynamoDB auto scaling. DynamoDB auto scaling adjusts capacity based on traffic patterns. Option A is incorrect because on-demand capacity is suitable for unpredictable workloads but may be more expensive. Option C is incorrect because DAX is a caching layer, not a scaling feature. Option D is incorrect because global tables are for multi-Region replication.

Answer

DynamoDB Accelerator (DAX)

Answer

DynamoDB on-demand capacity mode

Answer

DynamoDB global tables

Question 9

A company is migrating an on-premises Oracle database to Amazon RDS for Oracle. The database is 1 TB and has a large number of stored procedures and triggers. The migration must minimize application changes. Which migration approach should be used?

Accepted Answer

Use AWS Database Migration Service (AWS DMS) with full load and ongoing replication. AWS DMS with ongoing replication allows for minimal downtime and can migrate data while keeping the source database running. Option A is incorrect because expdp/impdp does not support ongoing replication. Option C is incorrect because using S3 as an intermediate step adds complexity. Option D is incorrect because AWS SCT is for schema conversion, not data migration.

Answer

Use AWS Schema Conversion Tool (AWS SCT) to convert the schema and AWS DMS for data migration

Answer

Use Oracle Data Pump (expdp/impdp) to export and import the database

Answer

Use AWS S3 to store the data and AWS Glue to transform and load into RDS

Question 10

A company is deploying a new web application on AWS. The application uses Amazon RDS for MySQL with a Multi-AZ deployment. The application team wants to reduce latency for read-heavy workloads. Which action should be taken?

Accepted Answer

Add a read replica in the same Region. Adding read replicas offloads read traffic from the primary instance, reducing latency. Option A is incorrect because increasing instance size may not significantly reduce read latency. Option B is incorrect because enabling Multi-AZ does not improve read performance. Option D is incorrect because switching to DynamoDB is a different database paradigm and may require application changes.

Answer

Enable Multi-AZ on the existing RDS instance

Answer

Increase the instance size of the primary RDS instance

Answer

Switch from RDS to Amazon DynamoDB with DAX

Question 11

A company needs to migrate a 5 TB Oracle database to Amazon Aurora PostgreSQL. The company has a limited maintenance window and requires the migration to be completed within a few hours. Which approach should be used?

Accepted Answer

Use AWS Database Migration Service (AWS DMS) to migrate the data. AWS DMS can handle large data migrations efficiently. Option A is incorrect because pg_dump is for PostgreSQL, not Oracle. Option C is incorrect because S3 is not suitable for direct database migration. Option D is incorrect because AWS SCT is for schema conversion, not data migration.

Answer

Use AWS Schema Conversion Tool (AWS SCT) to convert the schema and AWS DMS for data migration

Answer

Use pg_dump to export the Oracle database and pg_restore to import into Aurora

Answer

Use AWS S3 to store the data and AWS Glue to transform and load into Aurora

Question 12

A company is deploying a new application that requires a relational database with automatic failover and cross-Region disaster recovery. The application is read-heavy and expects up to 10 GB of data. Which combination of AWS services should be used?

Accepted Answer

Amazon Aurora with Multi-AZ and an Aurora global database. Aurora with Multi-AZ and cross-Region replica provides high availability and DR. Option A is incorrect because RDS Multi-AZ does not provide cross-Region DR. Option C is incorrect because S3 and Athena are not relational databases. Option D is incorrect because DynamoDB global tables are for NoSQL.

Answer

Amazon RDS for MySQL with Multi-AZ and a read replica in another Region

Answer

Amazon S3 with AWS Glue and Amazon Athena

Answer

Amazon DynamoDB with global tables

Question 13

A company is migrating a 500 GB SQL Server database to Amazon RDS for SQL Server. The database has a large number of stored procedures and triggers. The migration must have minimal downtime. Which approach should be used?

Accepted Answer

Use AWS Database Migration Service (AWS DMS) with full load and ongoing replication. AWS DMS with ongoing replication allows for minimal downtime. Option A is incorrect because backup/restore does not support ongoing replication. Option B is incorrect because S3 and Glue are not designed for database migration. Option C is incorrect because AWS SCT is for schema conversion, not data migration.

Answer

Use AWS Schema Conversion Tool (AWS SCT) to convert the schema and AWS DMS for data migration

Answer

Use AWS S3 to store the data and AWS Glue to transform and load into RDS

Answer

Use native SQL Server backup and restore to Amazon RDS

Question 14

A company is deploying a new microservices application on Amazon ECS. Each microservice needs its own database. Which AWS database service should be used to minimize operational overhead?

Accepted Answer

Amazon DynamoDB. Amazon DynamoDB is a fully managed NoSQL database that requires no server management. Option A is incorrect because RDS requires provisioning and managing instances. Option B is incorrect because Aurora is also managed but may be overkill for small datasets. Option D is incorrect because Redshift is a data warehouse.

Answer

Amazon Aurora

Answer

Amazon Redshift

Answer

Amazon RDS for MySQL

Question 15

A company is migrating an on-premises PostgreSQL database to Amazon RDS for PostgreSQL. The database is 2 TB and the migration must have minimal downtime. Which TWO AWS services should be used together to accomplish this?

Accepted Answer

AWS Schema Conversion Tool (AWS SCT). AWS DMS provides data migration with ongoing replication, and AWS SCT can help convert schema if needed, but for homogeneous migration, DMS alone is sufficient. However, the question asks for two services; the combination of DMS and SCT is commonly used for heterogeneous migrations. For homogeneous, DMS alone is enough, but SCT can still be used to assess schema compatibility. Option E is incorrect because CloudEndure is for server migration.

Answer

AWS CloudFormation

Answer

AWS DataSync

Answer

AWS CloudEndure Migration