fetchrow_arrayref returns a defined reference only if there are rows in the result set, if not it's undefined. So you just need to replace the "while" with something like 
if ( not( $ref ) ) { 
   print "No results\n";
} else { 
   # code to print results
}

[download]

If I may offer some observations about the way you're doing this:

(1) The variable $numFields would be better named $number_fields. See perlstyle. And you might want to change "$ref" to "$aref" to indicate what kind of reference it is (myself, I'd probably call it $row, though I think Conway prefers $row_ref).

(2) The C-style for loop over the fields might be clearer if done in a more perl like way, just for example: 

  my $result = join ", ", @{ $ref }; 
  print $result, "\n";

[download]

(3) Personally I lean towards fetchrow_hashref these days: the performance penalty on that was fixed a long time ago.

In reply to Re: how to determine of fetchrow_Arrayref is empty? by doom
in thread how to determine of fetchrow_Arrayref is empty? by poolboi

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