Table of Contents

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  1. Preface
  2. Introduction to Informatica Data Engineering Integration
  3. Mappings
  4. Mapping Optimization
  5. Sources
  6. Targets
  7. Transformations
  8. Python Transformation
  9. Data Preview
  10. Cluster Workflows
  11. Profiles
  12. Monitoring
  13. Hierarchical Data Processing
  14. Hierarchical Data Processing Configuration
  15. Hierarchical Data Processing with Schema Changes
  16. Intelligent Structure Models
  17. Blockchain
  18. Stateful Computing
  19. Appendix A: Connections Reference
  20. Appendix B: Data Type Reference
  21. Appendix C: Function Reference

Rules and Guidelines for Mappings on the Databricks Spark Engine

Rules and Guidelines for Mappings on the Databricks Spark Engine

A non-native environment like Databricks Spark uses distributed processing and processes data on different nodes. Each node does not have access to the data that is being processed on other nodes. As a result, the runtime engine might not be able to determine the order in which the data originated. So, when you run a mapping in a non-native environment and you run the same mapping in the native environment, both mappings return correct results, but the results might not be identical. For more information, see the .
Consider the following run-time differences on the Databricks Spark engine:
  • Set the optimizer level to none or minimal if a mapping validates but fails to run. If you set the optimizer level to use cost-based or semi-join optimization methods, the Data Integration Service ignores this at run-time and uses the default.
  • The run-time engine does not honor the early projection optimization method in all cases. If the Data Integration Service removes the links between unused ports, the run-time engine might reconnect the ports.
  • When you use the auto optimizer level, the early selection optimization method is enabled if the mapping contains any data source that supports pushing filters to the source on Spark or Databricks Spark engines. For more information about optimizer levels, see the
  • The run-time engine drops rejected rows even if you configure the mapping to forward rejected rows. The rejected rows are not written to the session log file.


Updated September 28, 2020