(Glue-2011) BW Transfer Rules

Introduction

With Datavard GLUE Transfer rules you can modify data during the extraction process. This process is similar to transfer routines within BW transformations. The functionality can be used for adjusting data, changing SAP abbreviations to more human-readable form, currency conversion, etc. You can find in this document some basic information about transfer rules and the current implementation. 

Transfer rules are set for each field separately. This functionality behaves as an end routine in BW transformations, where we change/adjust data stored in a target structure. You can find more information about transfer rules in the chapter (Glue-2011) Transfer Rules.

On this page, we focus on transfer rules specific for data extraction from BW objects. Of course, you can combine these BW specific rules with standard transfer rules, provided by Datavard GLUE.

Currently, the following transfer rules are supported for BW extractions:

  • Routine: Unique recordmode - similarly to standard routine, this transfer rule generates include for custom adjustment of data. However this routine contains a predefined implementation for suppressing duplicate rows with the same semantic key but different recordmode fields. Moreover, because this routine is specific for recordmode field present in Change log table, you can use it only for Change log delta type. Routine: Unique recordmode


Routine: Unique recordmode 

This transfer rule generates include for custom data adjustment, similarly to the standard routine. However, this routine contains implementation by default. Its function is to suppress duplicate entries with the identical semantic key but different recordmode value during data extraction from Change log table. 

This routine selects duplicates from the corresponding Change log table of extractor's InfoProvider, based on a semantic key that is also present in the underlying GLUE table. This means, that only fields of InfoProvider, that are also specified in the target GLUE table will be used in selection. The semantic key is then used in group by clause to determine duplicate entries. In case some key fields of the InfoProvider are omitted, multiple records of Change log table will be evaluated as duplicates. Also, recordmode parameter, specified in the delta is taken into account and used in the where clause. This means, that the routine searches for duplicates within records satisfying recordmode selection in delta parameters. You can find more information about the Change log delta type in the chapter Change log delta.

The duplicates are then stored in an internal table together with their frequency. When the extraction is running, the routine checks how many times the record with the same semantic key occurred and skips the whole record in case it is not the last one. The last record is considered to be the most actual record and is transferred. The routine reads duplicates only once when the first line of a particular activation request is being transferred.

Please be aware of the following:

  • This transfer rule is supported for Change log delta type only.
  • Although it is possible to specify more Routine: Unique recordmode routines within one extractor, it would bring no additional effect except performance impact 
  • There is a possibility to manually adjust code generated for this routine. However, it is not recommended, because the change might affect routine behavior. Therefore we recommend you to assign this routine to RECORDMODE field of the GLUE table.