Table of Contents

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  1. Preface
  2. Working with Transformations
  3. Aggregator Transformation
  4. Custom Transformation
  5. Custom Transformation Functions
  6. Data Masking Transformation
  7. Data Masking Examples
  8. Expression Transformation
  9. External Procedure Transformation
  10. Filter Transformation
  11. HTTP Transformation
  12. Identity Resolution Transformation
  13. Java Transformation
  14. Java Transformation API Reference
  15. Java Expressions
  16. Java Transformation Example
  17. Joiner Transformation
  18. Lookup Transformation
  19. Lookup Caches
  20. Dynamic Lookup Cache
  21. Normalizer Transformation
  22. Rank Transformation
  23. Router Transformation
  24. Sequence Generator Transformation
  25. Sorter Transformation
  26. Source Qualifier Transformation
  27. SQL Transformation
  28. Using the SQL Transformation in a Mapping
  29. Stored Procedure Transformation
  30. Transaction Control Transformation
  31. Union Transformation
  32. Unstructured Data Transformation
  33. Update Strategy Transformation
  34. XML Transformations

Transformation Guide

Transformation Guide

Exactly-Once Processing for Real-time Sessions

Exactly-Once Processing for Real-time Sessions

The Integration Service provides exactly-once delivery of messages of real-time sources with the SQL transformation. A real-time message has to be delivered once to the SQL transformation. If there is an interruption in processing, the Integration Service can recover without requiring the message to be sent again. If the message is sent again, the Integration Service does not run DML statements from the message twice. The Integration Service might run other SQL statements such as SELECT or SET again.
To perform exactly-once processing, the Integration Service stores a state of operations for a checkpoint in the PM_REC_STATE table. Each SQL transformation has a separate state of operations. Each SQL transformation maintains a consistent state and does not share connections. You must have high availability for exactly-once processing.
Use the following rules and guidelines for recovering real-time sessions with SQL transformations:
  • You must set the transformation scope to Transaction to enable recovery for a sessions that contains an SQL transformation.
  • You cannot include auto-commit, commit statements, or DDL statements in SQL queries.
  • You cannot enable HA recovery for an SQL transformation if it is a passive transformation, or if you configured it for dynamic connections or for Script Mode .
  • A session may fail when you enable recovery for the SQL transformation and the workflow is enabled for concurrent execution or the session runs in multiple partitions. A database deadlock might occur on the PM_REC_STATE table.

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