Slowly changing dimensions (SCD)

I think the best approach always depends on the business requirements and the nature of data changes. There are several SCD types, but the most commonly used are SCD Type 1 (overwrite), Type 2 (history tracking), and Type 3 (limited history tracking).

Type 1 is simple and updates records directly, losing historical data.

Type 2 preserves historical changes by adding new records with surrogate keys and effective date columns.

Type 3 maintains limited historical information using additional columns.

There are more advanced strategies include hybrid approaches, SCD Type 6, and temporal tables in modern SQL databases. ETL tools like ADF, SSIS, and dbt help automate SCD handling.

Check this guide Microsoft Docs on SCD and a practical guide on SCD implementation.

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Amira Bedhiafi1y ago
I think the best approach always depends on the business requirements and the nature of data changes. There are several SCD types, but the most commonly used are SCD Type 1 (overwrite), Type 2 (history tracking), and Type 3 (limited history tracking).

Type 1 is simple and updates records directly, losing historical data.

Type 2 preserves historical changes by adding new records with surrogate keys and effective date columns.

Type 3 maintains limited historical information using additional columns.

There are more advanced strategies include hybrid approaches, SCD Type 6, and temporal tables in modern SQL databases. ETL tools like ADF, SSIS, and dbt help automate SCD handling.

Check this guide Microsoft Docs on SCD and a practical guide on SCD implementation.
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