Reusable transformations can be used in multiple mappings.When u need to incorporate this transformation into maping,U add an instance of it to maping.Later if U change the definition of the transformation ,all instances of it inherit the changes.Since the instance of reusable transforamation is a pointer to that transforamtion,U can change the transforamation in the transformation developer,its instances automatically reflect these changes.This feature can save U great deal of work.
the transformation that can be reused is called a reusable transformation.
as the property suggests it has to be reused:
so for reusing we can do it in two different ways
1) by creating normal transformation and making it reusable by checking it in the check box of the properties of the edit transformation. 2) by using transformation developer, here what ever transformation is developed it is reusable, and it can be used in mapping designer where we can further change its properties, as per our requirement.
1. A reusable transformation can be used in multiple transformations 2.The designer stores each reusable transformation as metada separate from any mappings that use the transformation. 3. Every reusable transformation falls within a category of transformations available in the Designer 4.one can only create an External Procedure transformation as a reusable transformation.
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