For a Type 1 slowly changing dimension (SCD), what should you do when non-key attributes change?

In the context of Type 1 slowly changing dimensions (SCD), when non-key attributes change, the appropriate action is to update the existing record. This approach is fundamental to Type 1 SCD which is designed to overwrite old data with the new data. The rationale behind this method is to maintain the most current information without preserving historical data for non-key attributes.

When you update the existing record, the changes reflect real-time adjustments, ensuring that users always access the latest version of the data without any historical implications. This method is particularly useful when the goal is to simplify data analysis and reporting, where outdated details could lead to confusion or inaccuracies in decision-making.

Other options, such as inserting a new record or deleting the existing record, are more aligned with Type 2 or Type 3 slowly changing dimensions, which focus on maintaining history or different versions of data rather than just current state updates. Ignoring changes also contradicts the intent of keeping data accurate and relevant for analytical purposes.