Please advise on the the alternative sol

Question

When using the FM RZL_READ_DIR_LOCAL
i get the list for files name in the importing directory (let's say ITAB)
With the list of file name i need to chek whether the file name exit in table KNA1 for the field KUNNR
I firstly thought of
Loop at itab.
write itab-name into L_KUNNR.
select single kunnr
form KNA1
where itab-name = L_KUNNR.
if sy-subrc EQ 0.
*Message name is valid
endif.
endloop.
Since for every time file name that exist it is accessing the database KNA1 please advise way t make it more performance
Another alternative way is
Loop at itab.
write itab-name into itab_tmp-kunnr
append itab_tmp.
Endloop
select xxx into KNA1
for all entires in itab_tmp
where kunnr = itab_tmp-kunnr.
into i_knA1
Loop at itab_tmp
reat i_knA1 where i_kan1-kunnr = itab_tmp-KUNNR.
if sy-subrc EQ 0.
*Message name is valid
endif.
endloop

Answer 1

Hi,
Change code as:
Loop at itab.
condense  itab-name.
itab_tmp-kunnr = itab-name.
append itab_tmp.
clear itab_tmp.
Endloop
if not itab_tmp[] is initial.
select xxx
into table it_KNA1
from kna1
for all entires in itab_tmp
where kunnr = itab_tmp-kunnr.
endif.
Now all the entries present in  it_KNA1 are valid entries.