DBS-C01 Deployment and Migration Practice Test 4 — 15 Questions

Question 1

Which TWO of the following are valid considerations when migrating an on-premises Oracle database to Amazon RDS for Oracle using AWS DMS? (Select TWO.)

Accepted Answer

DMS can continue to replicate changes after the full load is complete until the cutover.. AWS DMS supports ongoing replication (change data capture, CDC) after the full load completes, allowing you to keep the target database synchronized with the source until you perform the cutover. This minimizes downtime because you can replicate ongoing changes from the on-premises Oracle database to Amazon RDS for Oracle, then stop all applications and switch over with only a brief interruption.

Answer

DMS automatically converts Oracle stored procedures to RDS for Oracle compatible code.

Answer

DMS automatically converts partitioned tables to non-partitioned tables.

Answer

DMS can migrate directly to Amazon RDS Custom for Oracle without any configuration changes.

Question 2

A company is migrating a 5 TB Microsoft SQL Server database to Amazon Aurora MySQL. The migration must be completed with minimal downtime. Which THREE steps should the company take? (Select THREE.)

Accepted Answer

Use AWS DMS to perform a full load and ongoing replication from SQL Server to Aurora.. AWS DMS (Database Migration Service) supports ongoing replication (change data capture) from Microsoft SQL Server to Amazon Aurora MySQL, enabling a full load followed by continuous sync of changes. This minimizes downtime by allowing the source database to remain operational until the final cutover, at which point the application switches to the Aurora writer endpoint.

Answer

Update the application connection string to point to the Aurora reader endpoint.

Answer

Create a read replica of the Aurora database in the same region.

Question 3

Which TWO of the following are valid methods to migrate an on-premises MySQL database to Amazon RDS for MySQL? (Select TWO.)

Accepted Answer

Use AWS DMS to migrate from on-premises MySQL to RDS.. AWS DMS (Database Migration Service) is a fully managed service designed to migrate databases to AWS with minimal downtime. It supports homogeneous migrations like MySQL to Amazon RDS for MySQL, handling schema conversion, data replication, and ongoing changes via change data capture (CDC). This makes option B a valid and recommended method for migrating an on-premises MySQL database to RDS.

Answer

Use pg_dump to export the data and import into RDS.

Answer

Use SQL Server Integration Services (SSIS) to migrate the data.

Answer

Use Oracle Data Pump to export the data and import into RDS.

Question 4

A company wants to migrate an on-premises Oracle database to Amazon RDS for Oracle with minimal downtime. Which AWS service should be used for the migration?

Accepted Answer

AWS Database Migration Service (DMS). AWS Database Migration Service (DMS) is the correct choice because it is specifically designed to migrate databases to AWS with minimal downtime by using ongoing replication (change data capture, CDC) from the source Oracle database to the target Amazon RDS for Oracle instance. DMS supports heterogeneous and homogeneous migrations, and for Oracle-to-Oracle migrations, it can use Oracle LogMiner or binary reader to capture changes continuously, allowing the source to remain operational during the migration.

Answer

AWS Systems Manager

Answer

AWS Schema Conversion Tool (SCT)

Answer

AWS Service Control Policies (SCP)

Question 5

A company is migrating a 2 TB MySQL database to Amazon Aurora MySQL. They need to minimize downtime and ensure data consistency. Which approach should be used?

Accepted Answer

Use AWS DMS with ongoing replication (CDC).. AWS DMS with ongoing replication (CDC) is the correct approach because it allows you to perform an initial full load of the 2 TB database while continuously capturing and applying changes from the source MySQL database. This minimizes downtime by keeping the target Aurora MySQL cluster nearly synchronized, and you only need to stop writes briefly during the final cutover to ensure data consistency.

Answer

Use mysqldump to export and import into Aurora.

Answer

Establish AWS Direct Connect and use MySQL replication.

Answer

Use AWS SCT to convert schema and data.

Question 6

An e-commerce company is migrating its PostgreSQL database to Amazon RDS for PostgreSQL. The database has multiple large tables (over 500 GB each) and the migration window is only 2 hours. Which strategy would be MOST effective to meet the time constraint?

Accepted Answer

Use AWS DMS with parallel load by splitting tables into multiple tasks.. AWS DMS with parallel load by splitting tables into multiple tasks allows concurrent data transfer across multiple threads, maximizing throughput for large tables. This approach directly addresses the 2-hour migration window by distributing the workload, whereas a single task would be bottlenecked by sequential processing. Parallel load is specifically designed for high-volume migrations where time is critical.

Answer

Use a single DMS task with full LOB mode.

Answer

Increase the RDS instance size and use pg_dump.

Answer

Use AWS SCT to optimize schema and then one DMS task.

Question 7

A company wants to migrate a self-hosted MongoDB database to Amazon DocumentDB. They need to convert the schema. Which AWS service should they use?

Accepted Answer

AWS Schema Conversion Tool (SCT). AWS Schema Conversion Tool (SCT) is the correct choice because it is specifically designed to convert database schemas from one engine to another, including from MongoDB to Amazon DocumentDB. SCT analyzes the source schema, identifies incompatible objects, and generates a target schema that is compatible with DocumentDB, handling data type mappings, index conversions, and other structural differences.

Answer

AWS Glue

Answer

AWS Database Migration Service (DMS)

Answer

Amazon Athena

Question 8

A company is migrating an on-premises SQL Server database to Amazon RDS for SQL Server. They need to minimize downtime and have a limited network bandwidth of 50 Mbps. The database size is 1 TB. What is the MOST effective approach?

Accepted Answer

Use AWS Snowball Edge to transfer initial load, then DMS for CDC.. The 1 TB database size combined with a 50 Mbps network bandwidth would require over 46 hours for the initial load, making a full network transfer impractical. AWS Snowball Edge allows you to transfer the initial 1 TB seed data offline via a physical appliance, bypassing bandwidth constraints. After the seed is loaded into RDS, AWS DMS with Change Data Capture (CDC) can then replicate ongoing changes over the network, minimizing downtime to only the final cutover window.

Answer

Use AWS DMS with CDC over the network.

Answer

Use AWS SCT to compress data before transfer.

Answer

Use native SQL Server backup and restore to Amazon S3.

Question 9

A company is migrating a 10 TB Oracle data warehouse to Amazon Redshift. They want to use AWS DMS for continuous replication. However, the migration is taking longer than expected due to LOB columns. What optimization should be applied?

Accepted Answer

Set MaxLobSize to a value like 64 KB to limit inline LOB transfer.. Setting MaxLobSize to a value like 64 KB instructs AWS DMS to treat LOBs smaller than that threshold as inline data, which is transferred more efficiently in the batch stream. This avoids the performance penalty of using FullLobMode, which transfers each LOB individually and can dramatically slow down continuous replication for large tables with many LOB columns.

Answer

Use AWS SCT to compress LOBs.

Answer

Enable FullLobMode to transfer all LOBs.

Answer

Increase the number of DMS tasks.

Question 10

A company is migrating an on-premises MySQL database to Amazon RDS for MySQL. They need to validate that the schema is compatible. Which AWS service should they use?

Accepted Answer

AWS Schema Conversion Tool (SCT). The AWS Schema Conversion Tool (SCT) is designed specifically to assess and convert database schemas from one engine to another, including on-premises MySQL to Amazon RDS for MySQL. It analyzes the source schema for compatibility issues, identifies unsupported features or deprecated syntax, and generates a detailed assessment report. This makes it the correct choice for validating schema compatibility before migration.

Answer

Amazon Inspector

Answer

AWS Database Migration Service (DMS)

Answer

AWS Trusted Advisor

Question 11

A company is migrating a PostgreSQL database to Amazon Aurora PostgreSQL. They have set up AWS DMS with change data capture (CDC). However, after the initial load, the CDC replication is experiencing high latency. What is the MOST likely cause?

Accepted Answer

The source database has large transactions that are not committed quickly.. Large uncommitted transactions on the source database cause DMS CDC to buffer changes until the transaction commits, leading to high latency. DMS must wait for the commit record before applying changes to the target Aurora instance, and during this time, CDC replication stalls, accumulating a backlog of changes.

Answer

The target Aurora instance has insufficient storage.

Answer

The DMS instance is using an older engine version.

Answer

The network bandwidth is too low.

Question 12

A company is migrating a 5 TB SQL Server database to Amazon RDS for SQL Server using AWS DMS. They are using Full LOB mode. The migration is failing with an error about memory allocation. What should they do to resolve this?

Accepted Answer

Increase the DMS replication instance class.. The memory allocation error in AWS DMS Full LOB mode occurs when the replication instance lacks sufficient memory to buffer LOB data. Increasing the replication instance class (option B) directly provides more memory, resolving the issue. Decreasing MaxLobSize (A) would truncate data, not fix allocation. Splitting the task (C) does not increase memory per instance. Enabling BatchApply (D) improves commit efficiency but does not address memory allocation for LOBs. Therefore, B is correct.

Answer

Decrease the MaxLobSize setting.

Answer

Split the migration into multiple DMS tasks.

Answer

Enable BatchApply on the DMS task.

Question 13

Which TWO of the following are required when migrating an on-premises Oracle database to Amazon RDS for Oracle using AWS DMS with change data capture (CDC)? (Select TWO.)

Accepted Answer

Use AWS SCT to assess schema compatibility.. AWS SCT (Schema Conversion Tool) is required to assess and convert the source Oracle schema to a format compatible with Amazon RDS for Oracle, ensuring that data types, indexes, and other objects are correctly mapped before migration. This step is critical because even though both are Oracle databases, differences in version, parameter settings, and storage engines can cause schema incompatibilities that DMS cannot handle automatically.

Answer

Create a full backup of the source database.

Answer

Set up Oracle Data Guard for replication.

Answer

Manually create target tables in RDS.

Question 14

Which THREE factors should be considered when choosing between a homogeneous migration and a heterogeneous migration to Amazon RDS? (Select THREE.)

Accepted Answer

Performance requirements of the target database.. A homogeneous migration (e.g., MySQL to RDS MySQL) typically requires minimal schema changes, preserves performance characteristics, and maintains existing licensing costs. A heterogeneous migration (e.g., Oracle to RDS PostgreSQL) requires schema conversion (validating schema compatibility), may require re-architecting to meet performance requirements due to different query optimizers, and can change licensing costs (e.g., eliminating Oracle licenses). Therefore, factors B, D, and E directly influence the choice between homogeneous and heterogeneous migrations.

Answer

Network latency between source and target.

Answer

Amount of application code changes needed.

Question 15

Which TWO AWS services can be used together to migrate an on-premises MySQL database to Amazon Aurora MySQL with minimal downtime? (Select TWO.)

Accepted Answer

AWS Schema Conversion Tool (SCT). AWS Database Migration Service (DMS) can perform continuous replication from an on-premises MySQL source to an Amazon Aurora MySQL target using change data capture (CDC), enabling near-zero downtime. The AWS Schema Conversion Tool (SCT) is used to assess and convert the source schema, including any incompatible objects, to ensure the Aurora target is ready for migration. Together, SCT handles schema transformation while DMS handles the ongoing data replication.

Answer

Amazon Route 53

Answer

AWS CloudFormation

Answer

AWS Global Accelerator