Tuesday, August 4, 2015

Converting Oracle DB format of date to SAP date format

There are many data flows picking up the data from "external database" based source systems in BW. One of most used DB system is Oracle. To connect BW system to Oracle DB a technology called DB Connect is very often used. As Oracle and SAP are different systems designed by two different companies there are many differences in there while comparing each other. The differences are there as well as from date and time related fields representation.

Therefore there are challenges while integrating data from Oracle DBs into SAP BW. Especially when converting date and time fields in Oracle and into format compatible with SAP BW. Let's take an Oracle date format for example. It has a format as DD-MMM-YY means it has 7 characters (e.g. today's date is represented by: 03-AUG-15). Whereas SAP format is 8 characters long in format YYYYMMDD (see Data Element SYDATUM; Domain SYDATS or Data Type DATS). If we just simply assign Oracle date field to SAP one it won't get proper data because the fields are not compatible.

Now; how to solve this? On SCN there are many discussions (e.g. here or here) on this. Most of it suggest parsing value as they come from Oracle and concatenate it at the end to field in SAP format of date. However this is not proper approach. The way how Oracle produce the format of the data field depends on national language settings (NLS) used with the database connection. Therefore the date field can come in many different flavors as per many configuration settings. What actually needs to be done is to force Oracle to produce the date field in desired format. This can be achieved by adding function TO_CHAR into e.g. SELECT statement while we extracting the data. E.g. a separate view can be created in Oracle to add TO_CHAR function. Such a SELECT statement would look like:

select  to_char(,'YYYYMMDD') as dat from where ;

For more information see:

518241 - DB Connect in BW for an external Oracle database

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