IDT(universe) over the ECC system

Hi All,

We have ECC, BW & BO in our landscape.  We have Enterprise BO 4.1 SP 9. BW 7.3 & ECC 6.0.

For few reports(WEBI), user want to see the data from ECC not from BW ( They want to save on data load time).

In case of BW, using OLAP connection i was able to create WEBI reports based on BEx as the datasource,

In case of ECC, i checked the blogs and know that we will not be able to use ECC table directly, we need to create

* Infoset Query

* ABAP Query

* Function module

Let me know, if my understanding is right?

Infoset query and ABAP Query i have knowledge.

Can someone update on how a "Function module" be used in ECC to pass data to the IDT?

Should be create RFC enabled FM(BAPI), Is there any document on the same.

Thanks.