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

Sequence Generator output fields

Sequence Generator output fields

The Sequence Generator transformation has two output fields, NEXTVAL and CURRVAL. In an
elastic mapping
, the transformation has one output field, NEXTVAL. You cannot edit or delete these fields.
You can connect a Sequence Generator transformation to any transformation. If the mapping contains both fields, you do not need to map both of the output fields. If you do not map one of the output fields, the
mapping
task ignores the unmapped field.

NEXTVAL field

Use the NEXTVAL field to generate a sequence of numbers based on the Initial Value and Increment By properties.
Map the NEXTVAL field to an input field in a Target transformation or other downstream transformation to generate a sequence of numbers. If you do not configure the Sequence Generator to cycle through the sequence, the NEXTVAL field generates sequence numbers up to the configured End Value.
If you map the NEXTVAL field to multiple transformations, the
mapping
task generates the same sequence or a unique sequence of numbers for each downstream transformation based on the mapping type and whether incoming fields are disabled.
The following table lists the situations where the Sequence Generator transformation generates the same sequence or a unique sequence of numbers:
Mapping type
Incoming fields are...
Same sequence or unique sequence?
Mapping
Not disabled
Same sequence
Mapping
Disabled
Unique sequence*
Elastic mapping
-
Same sequence
*
To generate the same sequence of numbers when incoming fields are disabled, you can place an Expression transformation between the Sequence Generator and the transformations to stage the sequence of numbers.

CURRVAL field

The CURRVAL field value is the NEXTVAL value plus the Increment By value. For example, if the Initial Value is 1 and Increment By is 1, the
mapping
task generates the following values for NEXTVAL and CURRVAL:
NEXTVAL
CURRVAL
1
2
2
3
3
4
4
5
5
6
Typically, you map the CURRVAL field when the NEXTVAL field is already mapped to a downstream transformation in the map. If you map the CURRVAL field without mapping the NEXTVAL field, the
mapping
task generates the same number for each row.