my $sth;
  for my $href (@array_of_hashrefs) {
     my @list = ('SELECT * FROM mytable WHERE', $href);
     my ($sql, @bind) = sql_interp @list;
     if (! defined $sth || $sth->{Statement} ne $sql) {
         $sth = $dbh->prepare($sql);
     }
     $sth->execute(@list); ###### <------ SAY WHAT?!!!!!
     $sth->fetchall_arrayref();
  }