In the near future you will be able to use HANA as your primary DB for ERP/Business Suite (you can already do this for BW). In this case you don't swap roles, but instead simply replace your current DBMS with HANA instead.
SAP also have ABAP Kernel Switch in Pilot. This automatically re-routes all read only SQL statements to the secondary DBMS when using HANA with Replication at the kernel level. This way you can redirect SQL operations without code changes.
Tags: Is it possible to use HANA DB as the primary DB & ABAP DB as secondary, ABAP Kernel Switch,
Labels: HANA DATABASE