Which option should be included when inserting new records for a Type 1 SCD?

Which option should be included when inserting new records for a Type 1 SCD?

• A. Maintain a history of changes.
• B. Insert only when the natural key is new.
• C. Overwrite the existing record only.
• D. Update the non-key attributes only.

Answer: (B)

When managing a Type 1 Slowly Changing Dimension (SCD), the key characteristic is that no historical data is preserved; the most current values for attributes are retained in the dimension table. This means that when a new record is inserted, it should occur only for those instances where the natural key, which uniquely identifies each record, is new to the table. This process ensures that updates replace any existing records linked to the same natural key without maintaining a history of prior values. In Type 1 SCD, when a change occurs, the existing record will be overwritten with the new values for non-key attributes. Therefore, attention to the uniqueness of the natural key is critical when inserting new records. This approach emphasizes updating records when changes happen, rather than inserting duplicates with the same natural key.

When managing a Type 1 Slowly Changing Dimension (SCD), the key characteristic is that no historical data is preserved; the most current values for attributes are retained in the dimension table. This means that when a new record is inserted, it should occur only for those instances where the natural key, which uniquely identifies each record, is new to the table. This process ensures that updates replace any existing records linked to the same natural key without maintaining a history of prior values.

In Type 1 SCD, when a change occurs, the existing record will be overwritten with the new values for non-key attributes. Therefore, attention to the uniqueness of the natural key is critical when inserting new records. This approach emphasizes updating records when changes happen, rather than inserting duplicates with the same natural key.