There's nothing inefficient in there. You could remove the useless || undef, since the value is already false and you check for true/false not defined/undefined.

sub get_name
{
  my $name = dblookup() || undef;
  $name;
}
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becomes

sub get_name
{
  my $name = dblookup();
  $name;
}
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becomes

sub get_name
{
  dblookup();
}
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becomes

*get_name = \&dblookup;
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As for the if, you could do

if ( my $name = get_name() )
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