If you just need to know if there are any results but don't need to fetch them, use SELECT COUNT(*). If you need to both read any results and do something if nothing was read, then you can use a flag to signal when you read anything: 
$sth->execute();
my $count = 0;
while (my $row = $sth->fetchrow_arrayref()) {
   process_row($row);
   $count++;
}
unless ($count) {
   do_something_else();
}

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In reply to Re: Determining if a DBI SELECT comes back empty by iburrell
in thread Determining if a DBI SELECT comes back empty by spacewarp

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