Table of Contents

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  1. Preface
  2. Using the Designer
  3. Working with Sources
  4. Working with Flat Files
  5. Working with Targets
  6. Mappings
  7. Mapplets
  8. Mapping Parameters and Variables
  9. Working with User-Defined Functions
  10. Using the Debugger
  11. Viewing Data Lineage
  12. Comparing Objects
  13. Managing Business Components
  14. Creating Cubes and Dimensions
  15. Using the Mapping Wizards
  16. POWERCENTERHELP
  17. Datatype Reference
  18. Configure the Web Browser

Rules and Guidelines for Propagating Ports and Attributes

Rules and Guidelines for Propagating Ports and Attributes

Use the following rules and guidelines when you propagate port attributes:
  • The Designer does not propagate to implicit dependencies within the same transformation.
  • When you propagate a port description, the Designer overwrites the description for the port in the other transformations in the mapping.
  • When you propagate backward along the link path, verify that the change does not cause the Integration Service to fail the session. For example, if you propagate changes to a source qualifier, the Integration Service might generate invalid SQL when it runs the session. If you change the port name “CUST_ID” to “CUSTOMER_ID,” the Integration Service might generate SQL to select the wrong column name if the source table uses “CUST_ID.”
  • When you propagate port attributes, verify that the change does not cause the Designer to invalidate the mapping. For example, when you change the datatype of a port from integer to string and propagate the datatype to other transformations, the Designer invalidates the mapping if a calculation uses one of the changed ports. Validate the mapping after you propagate ports. If the Designer invalidates the mapping, click Edit > Revert to Saved to revert to the last saved version of the mapping.
  • When you propagate multiple ports, and an expression or condition depends on more than one propagated port, the Designer does not propagate attributes to implicit dependencies if the attributes do not match.
    For example, you have the following expression in an Expression transformation:
    Item_desc_out = Substr(ITEM_NAME, 0, 6) || Substr(ITEM_DESC, 0, 6)
    The precision of Item_desc_out is 12, ITEM_NAME is 10, and ITEM_DESC is 10. You change the precision of ITEM_DESC to 15. You select parse expressions to infer dependencies and propagate the port attributes of ITEM_NAME and ITEM_DESC. The Designer does not update the precision of the Item_desc_out port in the Expression transformation since the ITEM_NAME and ITEM_DESC ports have different precisions.


Updated June 25, 2018