selecting data from data base tables into itab with multiple select queries
i am dealing with a situation where in there is 3 DB tables in all say
1. ITAB - ZTBL_MAIN.
2. DB table - ZTBL_SUB1.
3. DB table - ZTBL_SUB2.
ZTBL_MAIN contains feilds from both tables 2 and 3 so to choose some records from ZTBL_SUB1 into the ITAB a select query has been written as below.
SELECT * FROM ZTBL_SUB1 INTO CORRESPONDING FIELDS OF TABLE ZTBL_MAIN
now i also want some feilds in main for each record to be filled from the other DB table for which if i use another select query after the above one in my report prog. say..
SELECT * FROM ZTBL_SUB2 INTO CORRESPONDING FIELDS OF TABLE ZTBL_MAIN
then all the previous records are going to be erased..Kindly let me know a way in which i can implement the above implementation.