Which SCD type keeps the latest data, with old data overwritten?

Which SCD type keeps the latest data, with old data overwritten?

• A. Type 3 SCD
• B. Type 0 SCD
• C. Type 2 SCD
• D. Type 1 SCD

Answer: (D)

When you update a dimension attribute and you want to overwrite the old value, you're using Type 1 SCD. In this approach, the existing attribute value is updated in place, so only the most recent data is stored and no history is kept. If you need to remember changes, you’d use Type 2, which adds a new row for each change to preserve history, or Type 3, which stores a limited history in additional columns. Type 0 means no changes are allowed, which isn’t about overwriting with the latest data. So for keeping only the latest data and discarding the past, Type 1 is the correct fit.

When you update a dimension attribute and you want to overwrite the old value, you're using Type 1 SCD. In this approach, the existing attribute value is updated in place, so only the most recent data is stored and no history is kept. If you need to remember changes, you’d use Type 2, which adds a new row for each change to preserve history, or Type 3, which stores a limited history in additional columns. Type 0 means no changes are allowed, which isn’t about overwriting with the latest data. So for keeping only the latest data and discarding the past, Type 1 is the correct fit.