data: int_table_1 type standard table of int_table. "<< this is easy int_table_1 = int_table.
hits very less on the performance.. Infact very very little.. dont bother much about this... ABAP has some limitations.. you got to over come that with performance.. ABAP 7.0 is gonna over come with all these issue..
what is the large number you are talking about..? how big is the number?
To count number of records based upon any condition, use code:-
DATA : lines_count TYPE i. "for counting number of lines LOOP AT itab WHERE condition TRANSPORTING NO FIELDS. "this will not move any records into work area lines_count = lines_count + 1. "increment counter ENDLOOP. WRITE : / 'Lines :', lines_count. "print
Hope this solves your problem.
Thanks & Regards