It looks like $Line isn't getting a value assigned to it. I think your split command should have parentheses around the regexp:

my ($Line, $Filed, $Dvalue) = split(/\t/);
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If you're splitting a record on tabs, you might want to check if multiple tabs separate the fields. If so, you could use:

my ($Line, $Filed, $Dvalue) = split(/\t+/);
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I'm a beginner PERL user but I hope that helps.

Update: Changed /\t*/ to /\t+/ to avoid unexpected results. Thanks esper!