Four problems. (Aside from not previewing your node. Use <c>...</c> around code in your nodes.)

• You call your file handle TABLE, table and IN. The name is case-sensitive, and using the wrong name obviously won't work. Furthermore, you're better off using lexical file handles:

  open(my $fh, '<', $inputs)
     or die ...
  
  while (<$fh>) { ... }
  
  close($fh);  # Optional.
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• Similarly, you read each line into $line, yet you use $_ further on.

• Third, keep in mind that the lines returned by the <HANDLE> operator include a trailing newline. Use chomp($line); as the first line of the while loop if you wish to remove this newline.

• Finally, you treat $string as if it's a regexp while it's probably just text. (Added for clarification: If $string contains text as opposed to a regexp, you can convert the text to a regexp using \Q...\E or quotemeta. )

  if ($line =~ /\Q$string\E/) { ... }
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  If you want to check for equality:

  if ($line eq $string) { ... }
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