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Union Transformation
Why Union transformation is active while it returns same number of rows as in the sources?


  
Total Answers and Comments: 2 Last Update: June 22, 2008     Asked by: saurabh7385 
  
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April 04, 2008 04:43:54   #1  
suvomoy.chakraborty@patni.com Member Since: April 2006   Contribution: 1    

RE: Union Transformation

Union Transformation in general does not allow duplicate rows. If the sources contain duplicate rows then the effective count of rows after union certainly will be reduced. That should be one of the reasons for it being an active transformation.

A question may be raised regarding a situation where the sources do not contain any duplicates. The answer should be even in that scenario the transformation's inherent ability to check for the duplicate rows will remain intact. Just like a filter transformation not changing the row count because the filter condition was not either entirely true or entirely false for all of the rows.


 
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June 22, 2008 05:52:27   #2  
nandu214 Member Since: June 2008   Contribution: 0    

RE: Union Transformation
But union transformation doesn't delete the duplicate records when we are joining two tables i found this information in Informatica help.

can  anyone throw light on this.

 
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