how to capture Exception error message in Odata ?

Hi,

  I am new to sap gateway. Currently i am creating a Odata Service through the transaction SEGW. In the query i have mapped a RFC. When i execute the service sometimes the RFC throws exception like 'No data Found'. But i dont know how to capture the exception returned from the RFC.

I read some threads which says use

RAISE EXCEPTION TYPE /IWBEP/CX_MGW_BUSI_EXCEPTION

      EXPORTING
        textid            = /iwbep/cx_mgw_busi_exception=>business_error
        message       =  lv_text
        message_container = io_message_container.

My doubt is since i have not done any code in the DPC method. As said in many threads should i go to DPC_EXT method and redefine the method or how to capture the exception.

Kindly advise. Thanks in advance