Dear Monks,

Please could somebody suggest a way of improving the efficiency of this bit of code. One idea that I have is to sort the @Geo_areas array and then in the SQL statement use 'between the first and last element of the sorted array'. That would work in the context of the task. Could I execute a block of SQL statements? Would that be more efficient? Anyway perhaps I am being a bit premature in asking this question, as the code does not seem to be running as expected anyway. It is running at the moment but is not printing to an output file. 

 foreach (@Geo_areas) {

      $_ or next;

      my $Return_results = "Select * from Result_storage_keep where Ag
+gregated_area LIKE '".$_."' \;";
                
      my $sth_C = $dbh->prepare($Return_results) or die "Couldn't prep
+are query: ".$dbh->errstr;
      
      $sth_C->execute() or die "Couldn't execute query: ".$sth_C->errs
+tr;
      
    while (my @row = $sth_C->fetchrow_array) {
    foreach (@row) { 
      
      $_ = '' unless defined;
    }
    print OUTPUT_FILE join("\t", @row);
    print OUTPUT_FILE "\n";
    undef @row;
      }
  }

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In reply to while (my @row = $sth->fetchrow_array) by Win

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