I'm looking for advice on how to deal with comparing (in regards to similarity) documents. I've been checking out Text::Compare, and it seems to do the job quite nicely. However, my plead for advice and knowledge is a bit more "abstract". :)

First of, I want to describe my approach; 
# Create a list of files/documents that haven't been
# compared to the rest of the documents
my @new_docs = $foo->get_new_documents();
my @old_docs = $foo->get_old_documents();

# Process
my $Compare = Text::Compare->new( memoize => 1 );
foreach my $new_doc ( @new_docs ) {
    $Compare->first( $new_docs );
    foreach my $old_doc ( @old_docs ) {
        $Compare->second( $old_doc );
        $foo->save_similarity( $new_doc, $old_doc, $Compare->similarit
+y() );
    }
}

[download]
This works quite well, but you all understand that if there are 100,000 documents to compare against, it will take a lot of time. Is it possible to something "smart" to make it go faster?

My other question is; what is the best way to store the similarity info? Right now I have a document_similarity table which contains a pointer doc1_id and doc2_id (int, combined primary key) and a similarity field (float). This works, but are there smarter ways here as well?

Thanks in advance for any input!

In reply to Comparing text documents by Anonymous Monk

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