In what scenario would using external tables be most beneficial?

Using external tables is most beneficial for importing large volumes of data because they allow for efficient and effective management of data that resides outside the regular database environment. External tables can directly access and query data files, such as CSV or text files located on a file system or cloud storage, without the need to load that data into the database first. This capability is particularly advantageous when dealing with significant data sets, as it can reduce overhead and operational time associated with traditional data import methods.

In scenarios involving small data sets, real-time data synchronization, or quick access to local data files, leveraging external tables may not provide the same benefits. For smaller datasets, other methods might be faster and simpler. Real-time data synchronization might not align with the nature of external tables, which are typically used for batch operations rather than continuous streaming of data. Quick access to local data files could also be managed through simpler file I/O operations without the need for the additional complexity that external tables may introduce. Thus, utilizing external tables for handling large volumes aligns with performance optimization and resource management strategies in data warehousing and big data contexts.