"In the larger companies I have worked at as a data analyst, I have had to work with multiple data warehouses to retrieve the appropriate data. For a particular corporate-wide initiative, I queried against four different data warehouses. Once I retrieved the records and variables I needed, I built one large dataset I worked off of to complete my analysis."

This is an operational question that the interviewer uses to determine how you go about performing the duties required by this job. This specific question gives them an idea of the scope of work you've done in your previous roles. Keep your answer brief and to the point when responding to operational questions. The interviewer will ask you a follow-up question if they need additional information.