A team plans to query three systems - an operational database, an existing warehouse, and lakehouse tables - in a single report. What does federation in watsonx.data provide here?
Select an answer to reveal the explanation.
Short Explanation
You get one SQL interface and one governed catalog view across all three sources, so you can write the join without staging everything together first. You don’t get source conversion, cross-system transactions, or credential-free access.
Full Explanation
The correct answer is the one that describes one SQL interface and one governed catalog view across all three sources, allowing the join to be expressed without staging the sources together first. The value of federation in a multi-source report is unification of interface and governance. Analysts write one query, the engine reaches each source through its connector, and platform policy applies across the whole catalog surface, all without an intermediate staging step.
The option describing automatic conversion of the two external sources into open table formats on object storage is incorrect because federation reads sources as they are. Converting them to open table formats on object storage is ingestion, which is the other side of the fork.
The option describing a guarantee that the three sources are transactionally consistent at the moment of the query is incorrect because there is no cross-system transaction. Each source is read at its own point in time, and a report spanning three independent systems reflects three independent moments.
The option describing elimination of the need for credentials on the external systems is incorrect because every connector authenticates to its source. Federation centralises where those connections are configured; it does not remove the need for them.
For the exam, be able to name both what federation unifies, interface and governance, and what it does not, performance and cross-source consistency.