Table of Contents

Search

  1. Preface
  2. Transformations
  3. Source transformation
  4. Target transformation
  5. Aggregator transformation
  6. Cleanse transformation
  7. Data Masking transformation
  8. Deduplicate transformation
  9. Expression transformation
  10. Filter transformation
  11. Hierarchy Builder transformation
  12. Hierarchy Parser transformation
  13. Hierarchy Processor transformation
  14. Input transformation
  15. Java transformation
  16. Java transformation API reference
  17. Joiner transformation
  18. Labeler transformation
  19. Lookup transformation
  20. Mapplet transformation
  21. Normalizer transformation
  22. Output transformation
  23. Parse transformation
  24. Python transformation
  25. Rank transformation
  26. Router transformation
  27. Rule Specification transformation
  28. Sequence Generator transformation
  29. Sorter transformation
  30. SQL transformation
  31. Structure Parser transformation
  32. Transaction Control transformation
  33. Union transformation
  34. Velocity transformation
  35. Verifier transformation
  36. Web Services transformation

Transformations

Transformations

Group by fields

Group by fields

In an
elastic mapping
, you can use group by fields to define how to group data into partitions before the Java code runs.
When you configure a group by field, the
mapping
task groups rows with the same data into a partition. Then, the Java code runs for each partition in the transformation. For example, the input row behavior is processed for each partition and each row in the partition, and the end of data behavior is processed for each partition after processing all rows in the partition.
When you select more than one group by field, the task creates a partition for each unique combination of data in the group by fields.
If you do not configure a group by field, the Java code runs based on the data's default partitioning scheme.
If you use a parameter for the group by fields, define the group by fields when you run the mapping or when you configure the
mapping
task.