Wednesday 20 April 2011

SORTER TRANSFORMATION

 

                                                         

  • Connected and Active Transformation
  • The Sorter transformation allows us to sort data.
  • We can sort data in ascending or descending order according to a specified sort key.
  • We can also configure the Sorter transformation for case-sensitive sorting, and specify whether the output rows should be distinct.

When we create a Sorter transformation in a mapping, we specify one or more ports as a sort key and configure each sort key port to sort in ascending or descending order. We also configure sort criteria the Power Center Server applies to all sort key ports and the system resources it allocates to perform the sort operation.

The Sorter transformation contains only input/output ports. All data passing through the Sorter transformation is sorted according to a sort key. The sort key is one or more ports that we want to use as the sort criteria.

Sorter Transformation Properties

1. Sorter Cache Size:

The Power Center Server uses the Sorter Cache Size property to determine the maximum amount of memory it can allocate to perform the sort operation. The Power Center Server passes all incoming data into the Sorter transformation Before it performs the sort operation.

  • We can specify any amount between 1 MB and 4 GB for the Sorter cache size.
  • If it cannot allocate enough memory, the Power Center Server fails the Session.
  • For best performance, configure Sorter cache size with a value less than or equal to the amount of available physical RAM on the Power Center Server machine.
  • Informatica recommends allocating at least 8 MB of physical memory to sort data using the Sorter transformation.

2. Case Sensitive:

The Case Sensitive property determines whether the Power Center Server considers case when sorting data. When we enable the Case Sensitive property, the Power Center Server sorts uppercase characters higher than lowercase characters.

3. Work Directory

Directory Power Center Server uses to create temporary files while it sorts data.

4. Distinct:

Check this option if we want to remove duplicates. Sorter will sort data according to all the ports when it is selected.

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Example: Sorting data of EMP by ENAME

  • Source is EMP table.
  • Create a target table EMP_SORTER_EXAMPLE in target designer. Structure same as EMP table.
  • Create the shortcuts in your folder.

Creating Mapping:

1. Open folder where we want to create the mapping.

2. Click Tools -> Mapping Designer.

3. Click Mapping-> Create-> Give mapping name. Ex: m_sorter_example

4. Drag EMP from source in mapping.

5. Click Transformation -> Create -> Select Sorter from list. Give name and click Create. Now click done.

6. Pass ports from SQ_EMP to Sorter Transformation.

7. Edit Sorter Transformation. Go to Ports Tab

8. Select ENAME as sort key. CHECK mark on KEY in front of ENAME.

9. Click Properties Tab and Select Properties as needed.

10. Click Apply -> Ok.

11. Drag target table now.

12. Connect the output ports from Sorter to target table.

13. Click Mapping -> Validate

14. Repository -> Save

  • Create Session and Workflow as described earlier. Run the Workflow and see the data in target table.
  • Make sure to give connection information for all tables.

Sample Sorter Mapping :

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Performance Tuning:

Sorter transformation is used to sort the input data.

  1. While using the sorter transformation, configure sorter cache size to be larger than the input data size.
  2. Configure the sorter cache size setting to be larger than the input data size while Using sorter transformation.
  3. At the sorter transformation, use hash auto keys partitioning or hash user keys Partitioning.

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