Type 6 slowly changing dimension is described as a combination of Type 1, Type 2, and Type 3. Which option best reflects this statement?

Type 6 slowly changing dimension is described as a combination of Type 1, Type 2, and Type 3. Which option best reflects this statement?

• A. Type 0 SCD
• B. Type 4 SCD
• C. Type 1 SCD
• D. Type 6 SCD

Answer: (D)

Type 6 SCD is a hybrid approach that blends the behaviors of Type 1, Type 2, and Type 3 to deliver current values, full history, and a quick reference to the previous value in one design. Type 1 updates overwrite the current value with no built‑in history. Type 2 preserves history by creating new version rows for each change, so you can see all past states. Type 3 stores a limited history by keeping the previous value in a separate column, giving immediate access to the previous state without digging through history. Type 6 combines these ideas: you maintain full history (like Type 2) while also updating the present value (like Type 1) and enabling quick access to the immediately prior value (like Type 3) through dedicated columns. This lets you answer questions about the current state, the previous state, and the entire change history from the same dataset. For example, when a customer’s city changes, you can have a new version reflecting the new city, retain the old city value in a previous-value column, and use appropriate date or version fields to show the current row versus historical rows. This combination is what the statement describes, so the described pattern is the Type 6 slowly changing dimension.

Type 6 SCD is a hybrid approach that blends the behaviors of Type 1, Type 2, and Type 3 to deliver current values, full history, and a quick reference to the previous value in one design.

Type 1 updates overwrite the current value with no built‑in history. Type 2 preserves history by creating new version rows for each change, so you can see all past states. Type 3 stores a limited history by keeping the previous value in a separate column, giving immediate access to the previous state without digging through history.

Type 6 combines these ideas: you maintain full history (like Type 2) while also updating the present value (like Type 1) and enabling quick access to the immediately prior value (like Type 3) through dedicated columns. This lets you answer questions about the current state, the previous state, and the entire change history from the same dataset.

For example, when a customer’s city changes, you can have a new version reflecting the new city, retain the old city value in a previous-value column, and use appropriate date or version fields to show the current row versus historical rows. This combination is what the statement describes, so the described pattern is the Type 6 slowly changing dimension.