Hi there,
I would like to ask someone to confirm my understanding of table_comparison and in combination with Map_Operation.
Actually I thought that a table_comparison just compares the source and the target table and shows the differences. However , I made
my first tests and saw that the target table is directly updated.
I also saw in debug mode the operation codes internally created by the table_comparison.
In all my tests the content of the target table was actually replaced by the content of the source table. Would a SQL statement not be an easier solution to achieve this?
Then I added Map_Operation after the table_comparison and I understand that you can manipulate the internal operation codes provided by the table comparison before updating the target table.
For example: the TC detects 3 modified rows and triggers for these 3 rows the operation code "U".
Then you can specify in the Map_operation the conversion from 'Update' to 'Delete' if the business rule says that all rows that have been modified in the source table should be deleted in the target table.
Question 1: is my understanding correct?
Question 2: is there a transform that provides the result that I expected from table comparision?
I mean: compare 2 tables and and provide the difference between these tables without updating the tables_
the expected result should be a file with the different rows and indicator (U or I or D).
Or would a LookUp be the right way for this requirement?
Thanks for your support.
Andrzej