Table of Contents

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  1. Preface
  2. Transformations
  3. Source transformation
  4. Target transformation
  5. Access Policy transformation
  6. B2B transformation
  7. Aggregator transformation
  8. Cleanse transformation
  9. Data Masking transformation
  10. Data Services transformation
  11. Deduplicate transformation
  12. Expression transformation
  13. Filter transformation
  14. Hierarchy Builder transformation
  15. Hierarchy Parser transformation
  16. Hierarchy Processor transformation
  17. Input transformation
  18. Java transformation
  19. Java transformation API reference
  20. Joiner transformation
  21. Labeler transformation
  22. Lookup transformation
  23. Machine Learning transformation
  24. Mapplet transformation
  25. Normalizer transformation
  26. Output transformation
  27. Parse transformation
  28. Python transformation
  29. Rank transformation
  30. Router transformation
  31. Rule Specification transformation
  32. Sequence Generator transformation
  33. Sorter transformation
  34. SQL transformation
  35. Structure Parser transformation
  36. Transaction Control transformation
  37. Union transformation
  38. Velocity transformation
  39. Verifier transformation
  40. Web Services transformation

Transformations

Transformations

Persistent lookup cache

Persistent lookup cache

You can configure a Lookup transformation to use a persistent cache. When you use a persistent cache,
Data Integration
saves and reuses the cache files from mapping run to mapping run.
By default,
Data Integration
uses a non-persistent cache when you enable caching in a Lookup transformation. When you use a non-persistent cache,
Data Integration
deletes the cache files at the end of the mapping run. The next time you run the mapping,
Data Integration
builds the memory cache from the database.
If the lookup table does not change between mapping runs, you can use a persistent cache. A persistent cache can improve mapping performance because it eliminates the time required to read the lookup table. The first time that
Data Integration
runs a mapping using a persistent lookup cache, it saves the cache files to disk. The next time that
Data Integration
runs the mapping, it builds the memory cache from the cache files.
Configure the Lookup transformation to use a persistent lookup cache in the transformation advanced properties. To use a persistent cache, enable the
Lookup Cache Persistent
property.
You can configure the following options when you use a persistent cache:
Specify a name for the cache files.
When you use a persistent lookup cache, you can specify a name for the cache files.
To specify a name, enter the file name prefix in the
Cache File Name Prefix
field on the
Advanced
tab of the Lookup transformation. Do not enter a suffix such as .idx or .dat.
Rebuild the lookup cache.
If the lookup table changes occasionally, you can configure the Lookup transformation to rebuild the lookup cache. When you do this,
Data Integration
rebuilds the lookup cache from the lookup source when it first calls the Lookup transformation instance.
To configure the transformation to rebuild the cache, enable the
Re-cache from Lookup Source
property on the
Advanced
tab of the Lookup transformation.

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