internal table without headerline

hi,

I just started learning ABAP. I was struck up with this problem.

DATA : BEGIN OF str_mara,

Matnr LIKE MARA-MATNR,

END OF str_mara.

DATA : i_tab TYPE TABLE OF str_mara.

i declared internal table without headerline like this. now how can i write select query to fetch data from mara table and how can i display it??

plz help me,

thanks,