SAP Hana is not a database. In fact it is an application (or application server). You can create your data layer on it, and using SQL (not native) create your business logic in the database layer (in the application server). Later with a small learning curve you can develop services that expose the data in json (on the Hana) and generate presentation layers to this json with SAPUI5 (which is nothing more than a Google Angular.JS cousin).
In short, if your aim is to develop custom applications on SAP HANA, yes it is possible with a small learning curve. However if you want to migrate to SAP world, you need iterating several of the technologies involved... that are numerous: currently starting with ABAP and Fiori.
Best regards,
Angelo