Data Transformation: ETL Topics cont

• UPSERTS

• • INSERT/UPDATE is a common pattern in situations

• Process Everything or Just Changes

• • Deltas = Changes since last processing
  • Detected Deltas
  • • Compare Yesterday’s data to right now and build a list of changes
  • Application Managed Deltas
  • • Corresponding SOURCE_HISTORY table that has the data history
  • Database Managed Deltas
  • • Streams / Triggers