Append structure to standard table or create Z table?

Question

Nowadays SAP recommends to "keep the core clean" in order to be able to move to the cloud and always be able to update to the latest version without having to worry or retest, also valid for on-premise.

I got the requirement to add a Z field to the QMEL table to link its notifications to SAP PS projects (PROJ table). The QMEL table already has a structure -CI_QMEL- ready to be extended and the related BAPIs support this extension.

But in order to keep the core clean, I'm considering to challenge the functional requirement and suggest to create a ZNOTIF_PROJ table with the same key than QMEL (Notification ID). This would then become totally separated from the standard but at the same time the official BAPI wouldn't be able to support it, so a wrapper on top would be needed to update the standard and the custom and everything would become more complex.

Should I stick to the old extension style or go for a new table?

Answer 1

Personally I prefer extending standard tables. Having BAPIs, standard transactions, etc, work as expected is worth far more than a nebulous idea like a "clean core."

As long as you're not modding core code or extending tables in an incorrect manner, customizing the system in ways supported by SAP is not a bad thing. You should consider your future upgrade plans (S/4 on-prem vs cloud, for example) when deciding the right answer, but don't make things too hard on yourself.

Answer 2

S/4 on-prem or cloud already has adding new fields and tables functionality. We can do this in web UI look like SAP CRM. So there is no problem for extending existing structure. Help page about this functionality here .