Table of Contents

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  1. Preface
  2. Introduction to Transformations
  3. Transformation Ports
  4. Transformation Caches
  5. Address Validator Transformation
  6. Aggregator Transformation
  7. Association Transformation
  8. Bad Record Exception Transformation
  9. Case Converter Transformation
  10. Classifier Transformation
  11. Comparison Transformation
  12. Consolidation Transformation
  13. Data Masking Transformation
  14. Data Processor Transformation
  15. Decision Transformation
  16. Duplicate Record Exception Transformation
  17. Expression Transformation
  18. Filter Transformation
  19. Hierarchical to Relational Transformation
  20. Java Transformation
  21. Java Transformation API Reference
  22. Java Expressions
  23. Joiner Transformation
  24. Key Generator Transformation
  25. Labeler Transformation
  26. Lookup Transformation
  27. Lookup Caches
  28. Dynamic Lookup Cache
  29. Match Transformation
  30. Match Transformations in Field Analysis
  31. Match Transformations in Identity Analysis
  32. Normalizer Transformation
  33. Merge Transformation
  34. Parser Transformation
  35. Python Transformation
  36. Rank Transformation
  37. Read Transformation
  38. Relational to Hierarchical Transformation
  39. REST Web Service Consumer Transformation
  40. Router Transformation
  41. Sequence Generator Transformation
  42. Sorter Transformation
  43. SQL Transformation
  44. Standardizer Transformation
  45. Union Transformation
  46. Update Strategy Transformation
  47. Web Service Consumer Transformation
  48. Parsing Web Service SOAP Messages
  49. Generating Web Service SOAP Messages
  50. Weighted Average Transformation
  51. Window Transformation
  52. Write Transformation
  53. Appendix A: Transformation Delimiters

Developer Transformation Guide

Developer Transformation Guide

Connected and Unconnected Lookups

Connected and Unconnected Lookups

You can configure a connected Lookup transformation or an unconnected Lookup transformation. A connected Lookup transformation is a transformation that has input and output ports that you connect to other transformations in a mapping. An unconnected Lookup transformation appears in the mapping, but is not connected to other transformations.
An unconnected Lookup transformation receives input from the result of a :LKP expression in a transformation such as an Expression transformation or Aggregator transformation. The :LKP expression passes arguments to the Lookup transformation and receives a result back from the Lookup transformation. The :LKP expression can pass lookup results to another expression in the Expression or Aggregator transformation to filter results.
The following table lists the differences between connected and unconnected lookups:
Connected Lookup
Unconnected Lookup
Receives input values directly from the pipeline.
Receives input values from the result of a :LKP expression in another transformation.
Use a dynamic or static cache.
Use a static cache.
Cache includes the lookup source columns in the lookup condition and the lookup source columns that are output ports.
Cache includes all lookup and output ports in the lookup condition and the lookup/return port.
Returns multiple columns from the same row or insert into the dynamic lookup cache.
Returns one column from each row to a return port.
If there is no match for the lookup condition, the Integration Service returns the default value for all output ports. If you configure dynamic caching, the Integration Service inserts rows into the cache or leaves it unchanged.
If there is no match for the lookup condition, the Integration Service returns NULL.
If there is a match for the lookup condition, the Integration Service returns the result of the lookup condition for all lookup/output ports. If you configure dynamic caching, the Integration Service either updates the row the in the cache or leaves the row unchanged.
If a match occurs for the lookup condition, the Integration Service returns the result of the lookup condition to the return port.
Passes multiple output values to another transformation. Link lookup/output ports to another transformation.
Returns one output value to another transformation. The Lookup transformation return port passes the value to the port that contains the :LKP expression in the other transformation.
Supports user-defined default values.
Does not support user-defined default values.

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