Why is it important to analyze the impact of changes in a data migration system?

This is another operational question which the interviewer is using to determine the depth of your knowledge in this field. As the interview progresses, the questions will become more complicated and more specific. This signals that the interviewer is growing more confident in your abilities and is willing to investigate more complex topics.

"Examining the metadata associated with an object determines how it is impacted by a change in its structure or content. Changing data can break processes that are crucial to the function of the data warehouse. Allowing ad-hoc changes to data staging objects could be detrimental. Once a table is created in the staging area, you must perform an impact analysis before any changes are made to it. Many data migration tool vendors provide impact analysis functionality."