HI there, need help in thinking of a logic.

Question

Good Day!
I'm having trouble thinking of the logic in this simple (but tediously hard for me) problem.
I've got two internal tables, say table A and table B. I need to output records from table A that do not match records from table B. and vice versa.
The thing is, before I can output them, there are 3 primary keys for each table. let's say, ID, Document, and date. I need to match 3 of them to the other table, and if they don't match I would have to print them out.
What I did was.
Loop at TABLEA.
     Loop at TABLEB.
        IF TABLEA-ID NE TABLEB-ID AND ...
        WRITE TABLEA-ID ...
        ENDIF.
     ENDLOOP.
ENDLOOP.
The problem is,  let's say table a has
ID: 0
Doc:1
Date: 1
ID:1:
DOC:1
DATE:1
table b has
ID:1
DOC:1
DATE:1
and so on..
the loop will first compare table a with b and if it doesn't match well.. it prints it out immediately. Maybe the 1st record of table A is in the 20th record of table B. So I get multiple unmatches. So now I'm turning to the experts here, hope you guys can help.
I'm not sure if there was a faster way to do this. Any suggestions would be appreciated.
Edited by: Katrina Dy on Jul 2, 2008 8:56 AM

Answer 1

Hello
sort tablea by ID Document date.
sort tableb by ID Document date.
loop at tablea.
  read tableb with key ID = tablea-ID
                                Document = tablea-Document
                                date = tablea-date
                                binary search.
  if sy-subrc NE 0.
    write: tablea-ID, ...
  endif.
endloop.
loop at tableb.
  read tablea with key ID = tableb-ID
                                Document = tableb-Document
                                date = tableb-date
                                binary search.
  if sy-subrc NE 0.
    write: tableb-ID, ...
  endif.
endloop.