In the default configuration of the Autonomous Data Warehouse, which statement is true?

In the default configuration of the Autonomous Data Warehouse, the statement regarding the degree of parallelism being set based on the number of OCPUs in the system is accurate. This configuration reflects the optimized performance capabilities of the Autonomous Database, allowing it to handle workloads efficiently by leveraging the available OCPU resources.

The degree of parallelism is crucial for managing how many processes can work on the same query concurrently, which ultimately enhances the speed and efficiency of data processing and query execution. By aligning this setting with the number of OCPUs, the Autonomous Data Warehouse ensures that resources are utilized effectively, enabling the database to scale with the workload and maintain optimal performance levels.

In contrast, direct access to the database node and local file system, adding or modifying tablespaces, and ensuring that compression is enabled by default do not reflect the operational limitations and features of the Autonomous Data Warehouse's standard setup. Direct access is restricted to ensure security and stability, modifying database structures is not permitted for users due to the system's autonomous nature, and while compression is commonly used for efficient storage management, it is a feature that can vary based on specific configurations or use cases.