Pull the results off each table into arrays. Run a map over both arrays to increment the value of the key that matches the name. Bold if value > 1. 
my @table1 = GetNames( 'Table1');
my @table2 = GetNames( 'Table2');
my %names = ();
map {$names{$_}++} (@table1, @table2);
while (my ($name, $weight) =  each %names) {
  if ( $weight > 1 ) {
    PrintBoldly($name);
  } else {
    PrintNormally($name);
  }
}

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"One is enough. If you are acquainted with the principle, what do you care for the myriad instances and applications?"
- Henry David Thoreau, Walden

In reply to Re: Combining two fetches with DBI and MySQL by blogical
in thread Combining two fetches with DBI and MySQL by Anonymous Monk

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