Select from three tables (one field)

Question

Dear Friends
I have start-of-selection.
  select * from qals into corresponding fields of table itab where enstehdat in s_tarih.
  loop at itab.
      select matnr ntgew  from mara into (mara-matnr, mara-ntgew) where matnr eq itab-matnr.
      select matnr zfirmaadi ztezgah1 from zomt_malz into (zomt_malz-matnr, zomt_malz-zfirmaadi, zomt_malz-ztezgah1)
       where matnr eq itab-matnr.
        move-corresponding itab to itab2.
        itab2-zfirmaadi = zomt_malz-zfirmaadi.
        itab2-matnr = zomt_malz-matnr .
        itab2-ztezgah1 = zomt_malz-ztezgah1.
        itab2-ntgew = mara-ntgew.
        if sy-subrc = 0.
        append itab2.
        endif.
      endselect.
    endselect.
endloop.
end-of-selection.
And I want to get unique matnr from this qals,zomt_malz, mara .
Your helps will be very appreciated.

Answer 1

hi,
never use select statemnts inside loop.
use FOR ALL ENTRIES.
look this code.
select * from qals
into corresponding fields of table itab
where enstehdat in s_tarih.
select matnt ntgew
from mara
into table itab_mara
for all entries in itab
where
matnr = itab-matnr.
select matnr zfirmaadi ztezgah1
from zomt_malz into table itab_ ztezgah1
for all entries in itab
where
matnr = itab-matnr.
loop at itab.
move-corresponding itab to itab2.
read table itab_mara with key matnr = itab-matnr.
if sy-subrc = 0.
itab2-ntgew = mara-ntgew.
endif.
read table  itab_ ztezgah1 with key matnr = itab-matnr.
if sy-subrc = 0.
itab2-zfirmaadi = zomt_malz-zfirmaadi.
itab2-matnr = zomt_malz-matnr .
itab2-ztezgah1 = zomt_malz-ztezgah1.
endif.
append itab2.
clear itab2.
endloop.
regrds
anver
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