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Table of Contents

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  1. Preface
  2. Understanding Pipeline Partitioning
  3. Partition Points
  4. Partition Types
  5. Pushdown Optimization
  6. Pushdown Optimization and Transformations
  7. Real-time Processing
  8. Commit Points
  9. Row Error Logging
  10. Workflow Recovery
  11. Stopping and Aborting
  12. Concurrent Workflows
  13. Grid Processing
  14. Load Balancer
  15. Workflow Variables
  16. Parameters and Variables in Sessions
  17. Parameter Files
  18. FastExport
  19. External Loading
  20. FTP
  21. Session Caches
  22. Incremental Aggregation
  23. Session Log Interface
  24. Understanding Buffer Memory
  25. High Precision Data

Advanced Workflow Guide

Advanced Workflow Guide

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Incremental Aggregation

Incremental Aggregation

The first time you run an incremental aggregation session, the Integration Service processes the source. At the end of the session, the Integration Service stores the aggregated data in two cache files, the index and data cache files. The Integration Service saves the cache files in the cache file directory. The next time you run the session, the Integration Service aggregates the new rows with the cached aggregated values in the cache files.
When you run a session with an incremental Aggregator transformation, the Integration Service creates a backup of the Aggregator cache files in $PMCacheDir at the beginning of a session run. The Integration Service promotes the backup cache to the initial cache at the beginning of a session recovery run. The Integration Service cannot restore the backup cache file if the session aborts.
When you create multiple partitions in a session that uses incremental aggregation, the Integration Service creates one set of cache files for each partition.