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

Question 1

A company is migrating a 500 GB on-premises PostgreSQL database to Amazon RDS for PostgreSQL. The migration must have minimal downtime and support ongoing replication after the initial load. The network link has limited bandwidth, and the company wants to avoid costly data transfer fees. Which approach should be used?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

Use AWS DMS with ongoing replication (CDC) from the start.. AWS DMS with ongoing replication (CDC) enables a full load followed by continuous change data capture, which meets the requirements of minimal downtime and ongoing replication. DMS compresses data in transit and can throttle network usage, helping to manage limited bandwidth and avoid costly data transfer fees by using the existing network link efficiently.

Answer

Use AWS Database Migration Service (DMS) with a full load only, then cut over.

Answer

Use pg_dump to export the database and pg_restore to import into RDS.

Answer

Use AWS Snowball Edge to transfer the database files, then load into RDS.

Question 2

A team is using AWS DMS to migrate a 3 TB Oracle database to Amazon Aurora PostgreSQL. They configured the task as shown. After the full load completes, they notice that the target tables have no indexes, primary keys, or foreign keys. What is the most likely cause?

Accepted Answer

The TargetTablePrepMode is set to DROP_AND_CREATE, which creates tables without indexes or constraints.. When TargetTablePrepMode is set to DROP_AND_CREATE, AWS DMS drops the target table if it exists and then creates a new one using only the basic column definitions from the source. It does not migrate indexes, primary keys, or foreign keys because DMS is not designed to replicate schema objects beyond table structure and data. To preserve constraints and indexes, you must either pre-create them on the target or use a different prep mode like TRUNCATE_BEFORE_LOAD.

Answer

The migration task did not include transformation rules to create indexes and constraints.

Answer

The table selection rule uses wildcards and excludes system tables, which also excludes index definitions.

Answer

The task is using a full load without LOB support, which prevents index creation.

Question 3

A company is migrating a 2 TB MySQL database from on-premises to Amazon RDS for MySQL. They need to minimize downtime and ensure data consistency. They plan to use AWS DMS. What is the first step they should take before starting the migration task?

Accepted Answer

Enable binary logging (binlog) on the source MySQL database.. AWS DMS requires binary logging (binlog) to be enabled on the source MySQL database to capture ongoing changes during the full-load and change data capture (CDC) phase. This ensures data consistency and minimizes downtime by allowing DMS to replicate incremental changes after the initial load. Without binlog, DMS cannot perform CDC, and the migration would be limited to a one-time snapshot, risking data loss or extended downtime.

Answer

Create a read replica of the source database to reduce load.

Answer

Disable foreign key checks on the source database to speed up the load.

Answer

Enable binary logging on the target RDS for MySQL instance.

Question 4

A company is migrating a 500 GB MySQL database from on-premises to Amazon RDS for MySQL. The migration must have minimal downtime and support ongoing replication. Which AWS service should be used?

Accepted Answer

Use AWS Database Migration Service (DMS) with a full load and ongoing replication from a change data capture source.. AWS DMS is the correct choice because it supports both a full load of the 500 GB database and ongoing replication using change data capture (CDC) from the on-premises MySQL source. This enables minimal downtime by keeping the target RDS instance synchronized during the migration window, and it handles schema conversion automatically for MySQL-to-MySQL migrations without needing a separate tool.

Answer

Use mysqldump to export the database and import to RDS during a maintenance window.

Answer

Use AWS Schema Conversion Tool (SCT) to convert the schema and migrate data.

Answer

Take a physical backup, copy it to Amazon S3, and restore to RDS.

Question 5

Arrange the steps to enable automated backups for an Amazon RDS for PostgreSQL DB instance in the correct order.

Accepted Answer

Modify the DB instance → Set backup retention period to a value greater than 0 → Apply the changes immediately → Confirm the modification. Automated backups are enabled by adjusting the backup retention period in the instance settings and applying the change.

Answer

Set backup retention period to a value greater than 0 → Modify the DB instance → Apply the changes immediately → Confirm the modification

Answer

Modify the DB instance → Apply the changes immediately → Set backup retention period to a value greater than 0 → Confirm the modification

Answer

Confirm the modification → Modify the DB instance → Set backup retention period to a value greater than 0 → Apply the changes immediately

Question 6

Arrange the steps to configure a read replica for an Amazon RDS for PostgreSQL DB instance in a different AWS Region in the correct order.

Accepted Answer

Enable automatic backups on the source DB instance, then create a cross-Region read replica in the target Region, then monitor replication lag.. Cross-Region read replicas require backups enabled on the source, then creating a replica in another Region and monitoring lag.

Answer

Create a cross-Region read replica in the target Region, then enable automatic backups on the source DB instance, then monitor replication lag.

Answer

Monitor replication lag, then enable automatic backups on the source DB instance, then create a cross-Region read replica in the target Region.

Answer

Enable automatic backups on the source DB instance, then monitor replication lag, then create a cross-Region read replica in the target Region.

Question 7

A company is migrating an on-premises Oracle database to Amazon RDS for Oracle. The database has a large table with a BLOB column storing PDF files. Which migration approach minimizes downtime?

Accepted Answer

Use AWS Database Migration Service (DMS) with ongoing replication.. AWS DMS with ongoing replication (change data capture) allows you to perform an initial full load of the database while continuously capturing and applying changes from the source Oracle database to the target RDS for Oracle instance. This minimizes downtime because you can cut over to the new database after the initial load and replication lag is near zero, rather than taking the source offline for the entire migration.

Answer

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

Answer

Use Oracle RMAN to back up the database and restore to RDS.

Answer

Export the table without the BLOB column, then import the BLOBs separately.

Question 8

A company is migrating an on-premises MongoDB database to Amazon DocumentDB. The migration must be online with minimal downtime. The source MongoDB is version 4.0 and uses replica sets. Which tool should the company use?

Accepted Answer

Use AWS DMS with MongoDB as source and DocumentDB as target.. AWS DMS (Database Migration Service) supports continuous replication from MongoDB (including replica sets) to Amazon DocumentDB, enabling an online migration with minimal downtime. DMS uses the MongoDB oplog to capture ongoing changes, ensuring data consistency during the cutover. This is the only option that meets the requirement for an online migration with minimal downtime.

Answer

Use MongoDB Compass to export data and import into DocumentDB.

Answer

Use mongodump and mongorestore.

Answer

Create a read replica of the MongoDB replica set and promote to DocumentDB.

Question 9

A company wants to migrate its on-premises Oracle database to Amazon Aurora PostgreSQL. The company needs to convert the database schema and code from Oracle to PostgreSQL. Which AWS service should they use for schema conversion?

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, stored procedures, functions, and other code objects from one database engine to another, such as Oracle to Amazon Aurora PostgreSQL. It analyzes the source schema and generates a target schema with equivalent PostgreSQL syntax, handling data type mappings, PL/SQL to PL/pgSQL conversion, and other compatibility issues. AWS DMS handles data migration but does not perform schema or code conversion.

Answer

AWS DMS

Answer

AWS Glue

Answer

AWS Database Migration Service

Question 10

A company is migrating a 2 TB Oracle database from on-premises to Amazon RDS for Oracle. The network bandwidth is 100 Mbps. The migration must be completed within 3 days. Which approach is MOST efficient?

Accepted Answer

Use AWS DMS with parallel load and ongoing replication.. AWS DMS with parallel load and ongoing replication is the most efficient approach because it can handle the 2 TB migration within the 3-day window over a 100 Mbps link. At 100 Mbps, the theoretical maximum transfer is about 1.08 TB per day (100 Mbps * 86400 seconds / 8 bits per byte / 1024^4), so 2 TB would take nearly 2 days just for the full load. DMS's parallel load splits the data into multiple tasks, maximizing throughput and reducing the full-load time, while ongoing replication captures changes during the migration, allowing a seamless cutover without downtime.

Answer

Use Oracle RMAN to create a backup and restore to RDS.

Answer

Use Oracle Data Pump with a single export and import.

Answer

Use Oracle GoldenGate for real-time replication.

Question 11

A company is migrating an on-premises MySQL database to Amazon RDS for MySQL. The company wants to minimize application changes. Which endpoint type should the application use after migration?

Accepted Answer

RDS instance endpoint (DNS name). The RDS instance endpoint (DNS name) is the standard connection endpoint for a single RDS DB instance, which is the target of a direct migration from on-premises MySQL to Amazon RDS for MySQL. This endpoint requires no application changes, as the application simply replaces the old on-premises hostname with the RDS instance DNS name, maintaining the same MySQL protocol and connection logic.

Answer

RDS reader endpoint

Answer

RDS cluster endpoint

Answer

RDS console endpoint

Question 12

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.. Options B and E are correct because AWS DMS supports change data capture (CDC): after the initial full load completes, DMS reads the source Oracle redo/archive logs and applies ongoing changes to the RDS for Oracle target, which is exactly what option B describes, and this ongoing replication is what allows a low-downtime cutover as stated in option E. Both behaviors are core DMS capabilities for Oracle-to-RDS for Oracle migrations, using the Oracle LogMiner or Binary Reader method for CDC. Option A is wrong because DMS does not perform schema or PL/SQL code conversion; stored procedures, packages, and triggers must be handled separately with tools such as AWS SCT. Option C is wrong because DMS does not restructure partitioned tables into non-partitioned tables; it moves data, and any such schema transformation would be a manual or SCT task. Option D is wrong because RDS Custom for Oracle requires specific configuration, including the custom engine version, IAM instance profile, and VPC settings, so a migration cannot proceed with no configuration changes.

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 13

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.. Option B is correct because AWS Database Migration Service (DMS) natively supports MySQL as both a source and a target endpoint, allowing both one-time and ongoing (CDC) replication from on-premises MySQL into Amazon RDS for MySQL. Option E is correct because mysqldump is the standard MySQL-native logical backup utility; it produces SQL statements that can be piped or loaded directly into an RDS for MySQL instance, making it a valid migration method. Option A is incorrect because pg_dump is a PostgreSQL utility and cannot export MySQL data. Option C is incorrect because SQL Server Integration Services (SSIS) is a Microsoft SQL Server ETL tool, not a MySQL migration mechanism. Option D is incorrect because Oracle Data Pump (expdp/impdp) works only with Oracle databases and is incompatible with MySQL.

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 14

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 15

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.