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What is update strategy and what are the options for update strategy?



                                                                                                                                                                      
Scenario:
What is update strategy and what are the options for update strategy?

Solution:

Informatica processes the source data row-by-row. By default every row is marked to be inserted in the target table. If the row has to be updated/inserted based on some logic Update Strategy transformation is used. The condition can be specified in Update Strategy to mark the processed row for update or insert.

Following options are available for update strategy :


DD_INSERT : If this is used the Update Strategy flags the row for insertion. Equivalent numeric value of DD_INSERT is 0.
DD_UPDATE : If this is used the Update Strategy flags the row for update. Equivalent numeric value of DD_UPDATE is 1.
DD_DELETE : If this is used the Update Strategy flags the row for deletion. Equivalent numeric value of DD_DELETE is 2.
DD_REJECT : If this is used the Update Strategy flags the row for rejection. Equivalent numeric value of DD_REJECT is 3.


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