SMARTFORMS - Data fetching from Four tables

Hi gurus / experts,

I am a beginner for Smartforms. I have created a SAP SCRIPT to join Four tables (MSEG, MAKT, MARD & MKPF) and Driver program to execute this SAP Script.

Now I want to use same concept in SMART FORM. Will anyone tell me step by step procedure to join four tables in smartform creation of a driver program for it...

My SAP Script select statement is: 

parameters: PLANT like MSEG-WERKS obligatory.

parameters: DOCUMENT like MSEG-MBLNR obligatory.

parameters: YEAR like MSEG-GJAHR obligatory.

select MSEG_{ZEILE MSEG}MATNR MAKT_{MAKTX MSEG}CHARG MSEG_{MENGE MSEG}MEINS MSEG~EBELN

MSEG_{LIFNR MSEG}LGORT MSEG_{SGTXT MARD}LGPBE LFA1_{NAME1 MKPF}BLDAT MKPF~BUDAT into

corresponding fields of table itab FROM MSEG

inner join MAKT on MSEG_{MATNR = MAKT}MATNR

INNER JOIN MARD ON MSEG_{WERKS = MARD}WERKS AND MSEG_{LGORT = MARD}LGORT and MSEG_{MATNR = MARD}MATNR

INNER JOIN LFA1 ON MSEG_{LIFNR  = LFA1}LIFNR

INNER JOIN MKPF ON MSEG_{MBLNR = MKPF}MBLNR and MSEG_{GJAHR = MKPF}MJAHR

where MSEG_{WERKS = PLANT and MSEG}MBLNR = DOCUMENT and MSEG_{GJAHR = YEAR order by MSEG}ZEILE.

With thanks & Regards,

DSC