Introduction
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- Direct assignment – just copies one to one data from a source field to a target field
- Currency – a transformation of currency values according to a currency key
- Routine – custom implementation which changes the value in the selected field
Business function – adjust values with business functions
- Data enrichment –
- Meaningful field values – translation of values according to a domain, mapping table, SID or a custom conversion routine
- Routine: Unique recordmode - similarly to standard routine, this transfer rule generates include for custom adjustment of data. However this routine contains predefined implementation for suppressing duplicate rows with the same semantic key but different recordmode field. Moreover, because this routine is specific for recordmode field present in Change log table, you can use it only for Change log delta type. This routine is described on page (GLUE-1905) BW Transfer Rules
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In the case that a value in a particular field needs to be changed, deleted or adjusted, you can create your custom ABAP code, which will be then processed for the selected field during the load. To perform these changes:
Select Routine as a transfer rule and a click 
in the column Edit Rule to access a generated form. The form can be edited in the same way as any Z*/Y* ABAP report. Importing parameter is_record contains the whole record which is processed. This parameter should not be modified. You can change the value of the selected field through the parameter cv_field which modifies the value according to your requirements.
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Skip the records during the extraction process
You have an option to set up a condition to skip records during the extraction process. To perform this, you should set the flag 'gv_skip_line' under your condition.
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