Sample needed to query BW cube

I have two BW(BPC) cubes which are HANA enabled. I have heavy data processing logic currently in BADI and I am trying to push that into HANA DB layer, possibly as a SQL procedure.

1) Can someone point me to some sample/direction to achieve this

2) Any samples on how to query BW cubes and update them back

3) Is this the right forum for this question?

Appreciate any leads

~Dilkins