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  1. Preface
  2. Mappings
  3. Mapplets
  4. Mapping Parameters
  5. Where to Assign Parameters
  6. Mapping Outputs
  7. Generate a Mapping from an SQL Query
  8. Dynamic Mappings
  9. How to Develop and Run a Dynamic Mapping
  10. Dynamic Mapping Use Cases
  11. Mapping Administration
  12. Export to PowerCenter
  13. Import From PowerCenter
  14. Performance Tuning
  15. Pushdown Optimization
  16. Partitioned Mappings
  17. Developer Tool Naming Conventions

Developer Mapping Guide

Developer Mapping Guide

Dynamic Ports and Generated Ports

Dynamic Ports and Generated Ports

You can create dynamic ports in a transformation to receive new or changed columns from an upstream transformation. A dynamic port receives one or more columns and generates ports based on input rules. The input rules determine the columns that a dynamic port receives and generates.
Use dynamic ports to perform the following tasks:
Receive new and changed columns.
To get data from a dynamic source or a parameterized source, create a dynamic port in the downstream transformations to receive new and changed columns. If a mapping contains from a dynamic source, the dynamic ports in the downstream transformations automatically get any new or changed columns. For example, if a new column "title" is added to the dynamic source, the Read transformation passes the new column to the dynamic port and the dynamic port creates a generated port for the "title" column.
Filter columns based on input rules.
To process only a certain type of column in a transformation, create a dynamic port and define input rules to filter columns. For example, a mapping source has columns with decimal, string, and date/time data types. You need to process data only for columns of decimal data type. Create a dynamic port and define input rules to include only decimal columns.
Repeat a calculation for more than one port in an Expression transformation
To perform the same calculation on more than one port, use dynamic ports in dynamic expressions. A dynamic expression runs one time for each port in the dynamic port and returns the result to a dynamic output port.
The following image shows a dynamic port named From_Read_Employee and the generated ports:
A mapping contains a Read transformation and a Sorter transformation. The dynamic port From_Read_Employee in the Sorter transformation contains all the ports from the Read transformation as generated ports.

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