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Dynamic Look up in Informatica

We will be having a dilemma that when should we go for  dynamic lookup so let us discuss about that first. When we create a lookup on a target table and we are sure that there will be no duplicates coming from source data on PK Combination we go for a static cache lookup. But when there are duplicates coming from source end and we need to pick a latest value from the set then we go for dynamic look up. let me brief you with an example data

Name   Location
AAA    IND
BBB     USA
CCC     EUR
AAA    EUR

suppose we have data in the above following manner and only latest records should be pulled into the target so that the target data should look like in the following manner

Name Location
AAA  EUR
BBB   USA
CCC   EUR

When we select dynamic cache in look up properties a new column named as NewLookupRow gets added in ports section of look up.




Then we need select Insert else Update and Update else insert option.

The Newlook up row when the value returns as 0 means there is no change in data
The Newlook up row when the value returns as 1 means row should be inserted
The Newlook up row when the value returns as 2 means row should be updated

In the flow at router juncture we can give NewLookupRow=1 as insert condition and NewLookupRow=2 for updating records

Hope this article helps you in understanding Dynamic look up concept




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