1Z0-1123-25 Question 145
Select 2You are planning to migrate a 15 TB on-premises Oracle Database 19c to an Exadata Cloud Service in OCI. The business requires minimal downtime and data consistency must be maintained throughout the migration. Which two methods are recommended for achieving these requirements?
- A
Oracle Data Pump
- B
Oracle Zero Downtime Migration (ZDM)
- C
Oracle GoldenGate
- D
Cross-Platform Transportable Tablespaces with RMAN
Show answer and explanation
Correct answers: B, C
Explanation
For migrations needing minimal downtime and high data consistency, Oracle Zero Downtime Migration (ZDM) and Oracle GoldenGate are strongly recommended. ZDM automates the process of moving data while the production database remains online, effectively reducing downtime to a final cutover. GoldenGate enables continuous change data capture and replication, allowing you to synchronize the databases until you are ready to switch over. Oracle Data Pump and Cross-Platform Transportable Tablespaces are useful for many migration scenarios but typically involve a longer downtime window. Refer to the Oracle Zero Downtime Migration and Oracle GoldenGate documentation for best practices and detailed instructions.
- A. Incorrect.
Oracle Data Pump: Although Data Pump is a powerful tool for migrating smaller databases or for refreshing non-critical environments, it typically involves an export/import process that can lead to noticeable downtime. This makes it less optimal for large, mission-critical databases demanding minimal downtime.
- B. Correct.
Oracle Zero Downtime Migration (ZDM): ZDM is designed to automate and streamline migrations to OCI Database Services with nearly no downtime. It uses a combination of Oracle tools (like RMAN and Oracle GoldenGate) under the hood, coordinating the processes so you can keep the source database online until the final switch-over. This is correct for minimal downtime and data consistency.
- C. Correct.
Oracle GoldenGate: GoldenGate is a real-time data replication solution that allows you to continuously synchronize changes between on-premises and cloud databases. By maintaining near-real-time data synchronization, you can minimize the cutover window significantly, making it an excellent choice for scenarios that demand minimal downtime and data consistency. This is a correct choice.
- D. Incorrect.
Cross-Platform Transportable Tablespaces with RMAN: Transportable tablespaces can speed up the migration of very large databases, but it usually involves some downtime while the data is moved and metadata is imported. Also, additional steps are required to handle cross-endian conversions if the source and target platforms differ. It� not the best method for near-zero downtime scenarios.