(coreutils.info)Set operations

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Enter node , (file) or (file)node

8.3.6 Union, Intersection and Difference of files
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Combine ‘sort’, ‘uniq’ and ‘join’ to perform the equivalent of set
operations on files:

Command                              outcome
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‘sort -u file1 file2’                Union of unsorted files
                                     
‘sort file1 file2 | uniq -d’         Intersection of unsorted files
                                     
‘sort file1 file1 file2 | uniq’      Difference of unsorted files
                                     
‘sort file1 file2 | uniq -u’         Symmetric Difference of unsorted
                                     files
                                     
‘join -t'' -a1 -a2 file1 file2’      Union of sorted files
                                     
‘join -t'' file1 file2’              Intersection of sorted files
                                     
‘join -t'' -v2 file1 file2’          Difference of sorted files
                                     
‘join -t'' -v1 -v2 file1 file2’      Symmetric Difference of sorted
                                     files
                                     

   All examples above operate on entire lines and not on specific
fields: ‘sort’ without ‘-k’ and ‘join -t''’ both consider entire lines
as the key.