Table of Contents

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  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

Expression macros

Expression macros

An expression macro is a macro that you use to create repetitive or complex expressions in mappings.
You can use an expression macro to perform calculations across a set of fields or constants. For example, you might use an expression macro to replace null values in a set of fields or to label items based on a set of sales ranges.
In an expression macro, one or more input fields represent source data for the macro. An expression represents the calculations that you want to perform. And an output field represents the results of the calculations.
At run time, the task expands the expression to include all of the input fields and constants, and then writes the results to the output fields.
You can create expression macros in Expression and Aggregator transformations but you cannot combine an expression macro and an in-out parameter in an Expression transformation.