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 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
  26. POWERCENTERHELP

Advanced Workflow Guide

Advanced Workflow Guide

Hash Auto-Keys Partition Type

Hash Auto-Keys Partition Type

Use hash auto-keys partitioning at or before Rank, Sorter, Joiner, and unsorted Aggregator transformations to ensure that rows are grouped properly before they enter these transformations.
The following figure shows a mapping with hash auto-keys partitioning. The Integration Service distributes rows to each partition according to group before they enter the Sorter and Aggregator transformations:
This mapping includes a flat file source, a series of transformations including a Sorter and Aggregator transformation, and an Oracle target.
In this mapping, the Sorter transformation sorts items by item description. If items with the same description exist in more than one source file, each partition will contain items with the same description. Without hash auto-keys partitioning, the Aggregator transformation might calculate average costs and prices for each item incorrectly.
To prevent errors in the cost and prices calculations, set a partition point at the Sorter transformation and set the partition type to hash auto-keys. When you do this, the Integration Service redistributes the data so that all items with the same description reach the Sorter and Aggregator transformations in a single partition.


Updated July 04, 2018