Data Warehouse · ETL using SSDB · Microsoft Data Technology · Microsoft SSDB · Microsoft SSIS

SSDB – Part 4. ETL – Slowly Changing Dimension SCD Type 2 and 3

Tracking Changes over Time with SCD Type 2 and 3:

Incremental Loading

Incremental loading is an option that works well with large tables of data or when you wish to preserve the original values in your data.

Incremental loading compares values between the source and destination tables. Using that comparison, you can program the following tasks:

  • Add new rows that are found in the source but not in the destination
  • Update rows in the destination that are changed in the source
  • Delete (or flag) rows from the destination that are removed in the source

You can use a number of techniques to program these tasks. The SQL Merge command is the most efficient method.

Note: Microsoft is the owner of the content and video in this blog post.

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s