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

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.