I'm not sure if I am understanding your question correctly, but it seems like you're just looking for a way to split the '+' delimited query string into an array? If this is the case, all you'd need to do is

my @job_ids = split(/\+/, $ENV{'QUERY_STRING'});
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Then, you can do database queries, create text links, etc., on each of the @job_ids. Let me know if I'm grossly misunderstanding your question.