I am trying to run me script in the background. I connect to a mysql db using: my $db = DBI->connect($dsn, $user, $pw,{'PrintError' => 1, 'RaiseError' => 1}) or die "Unable to connect: $DBI::errstr\n"; When i run the script (either in the background or manually) I receive this error:
DBD::mysql::st fetchrow_array failed: fetch() without execute() at has
+-download-0.1.pl line 82.
DBD::mysql::st fetchrow_array failed: fetch() without execute() at has
+-download-0.1.pl line 82.

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Then the script fails and goes no further. The line that spawns the error:
#~ Update status to 2
            $query = "select status, dataid from radar_data where data
+type=$data_type and hasid ='$HAS_break[5]';";
            $query_handle = $db->prepare($query);
            $query_handle->execute();
            while(my @row = $query_handle->fetchrow_array()) {

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is not the first execute. Prior to the error I prepare and execute another query that goes without error. Not sure what the problem is and am wondering if anyone has any ideas?

the entire scripts (with commented error location):

#!/usr/local/bin/perl -w
use strict;
use Mail::Box::Manager;
use HTML::TreeBuilder;
use Proc::Background;
use DBI;
use DBD::mysql;
#~ use lib '/usr/local/lib/perl5/site_perl/5.10.0/';

my $dataid;
my $query;
my $query_handle;
my $data_type;
my $format;
my $cmd;
my $mailspool = "/var/spool/mail/thor";
my $tmpfldr = "/home/thor/tmp";
my $mgr = Mail::Box::Manager->new;
my $folder = $mgr->open(folder => $mailspool, access => 'rw');
my @HAS;

#~ DBI variables
my $host = "localhost";
my $database = "thor";
my $user = "thor";
my $pw = "*******";
my $port = 22;
my $dsn = "DBI:mysql:database=$database;host=$host;port=$port";
my $db = DBI->connect($dsn, $user, $pw,{'PrintError' => 1, 'RaiseError
+' => 1}) or die "Unable to connect: $DBI::errstr\n";
    
if (defined($folder)){
    my $emails = $folder->messages;
    print "There are $emails in $mailspool\n\nSearching For HAS URLs..
+.\n";
    foreach my $message ($folder->messages) {
        my $subject = $message->get('Subject');
        if ($subject =~ /^HAS\sData\sRequest:\sHAS\d{9}\sCompleted/){
            #~ print "$subject\n";
            my $body = $message->body;
            my @body = split(/\n/,$body);
            foreach my $string (@body){
                next if $string !~ /^http:/;
                #~ print "$string\n\n";
                push(@HAS,$string);
            }
        }
        #~ Need Root access to delete
        $message->delete;
    }
    $folder->close;
    
    if (my $hasnum = @HAS == 0) {
        print "\nThere are No Messages in the folder: $mailspool\n";
        exit;
    }
    
    print "HAS URLs Stored: @HAS\n";
    
    foreach my $HAS (@HAS){
        my @hrefs;
        
        #~ Get the HAS number
        my @HAS_break = split(/\//,$HAS);
        
        #~ Search Database for HAS number
        #~ Retreive Data Type
        $query = "select datatype from radar_data where hasid ='$HAS_b
+reak[5]' limit 1;";
        $query_handle = $db->prepare($query);
        $query_handle->execute();
        $query_handle->bind_columns(\$data_type);
        $query_handle->fetch();
        
        #~ $data_type = to_int($data_type);
        
        #~ print "$data_type\n";
        
        #~ Update status to 2
        $query = "select status, dataid from radar_data where datatype
+=$data_type and hasid ='$HAS_break[5]';";
        $query_handle = $db->prepare($query);
        $query_handle->execute();
        while(my @row = $query_handle->fetchrow_array()) { #ERROR HERE
            
            #~ Update only available data to 'Email Received' status
            if ($row[0] eq '1') {
                $query = "update radar_data set status=2 where dataid=
+$row[1] and datatype=$data_type and hasid ='$HAS_break[5]';";
                $query_handle = $db->prepare($query);
                $query_handle->execute();
            }
        } 

        print "Data type for $HAS: Level $data_type\n";
        
        $format = "/thordata1/nexrad/NIDS" if $data_type eq '3';
        $format = "/thordata1/Level2" if $data_type eq '2';
        
        #~ print "$data_type\n";
        print "Using Directory: $format\n";
    
        #~ Create HAS directory
        $cmd = "mkdir $format/$HAS_break[5]";
        print "$cmd\n";
        system($cmd);
        
        #~ Download HAS files
        $cmd = "wget $HAS -O $tmpfldr/index.html";
        print "$cmd\n";
        system($cmd);
        
        #~ Parse the html from NCDC
        my $tree = HTML::TreeBuilder->new_from_file("$tmpfldr/index.ht
+ml") or die "Cant build tree: $!\n";
        my @anchors = $tree->look_down(_tag => q{a});
        #~ print "@anchors\n";
        foreach my $anchor (@anchors) {
            if ($anchor->as_text =~ /\.tar/) {
                push @hrefs, $anchor->attr(q{href});
                print "File Available: ",$anchor->as_text,"\n";
            }
        }
        
        #~ Download Files
        foreach my $hrefs (@hrefs) {
            $cmd = "wget $HAS$hrefs -O $format/$HAS_break[5]/$hrefs";
            print "$cmd\n";
            system($cmd);
        }
        
        #~ Update status to 3
        $query = "select status, dataid from radar_data where datatype
+=$data_type and hasid ='$HAS_break[5]';";
        $query_handle = $db->prepare($query);
        $query_handle->execute();
        while(my @row = $query_handle->fetchrow_array()) {
            #~ Update only available data to 'Downloaded' status
            if ($row[0] eq '2') {
                $query = "update radar_data set status=3 where dataid=
+$row[1] and datatype=$data_type and hasid ='$HAS_break[5]';";
                $query_handle = $db->prepare($query);
                $query_handle->execute();
            }   
        } 

        #~ Delete temp file/html
        $cmd = "rm -rf /research/SSRG/ThOR/tmp/index.html";
        print "$cmd\n";
        system($cmd);
        
        #~ Start a background process and pass the data type to it to 
+mine the downloaded data
        my $command = "nohup /usr/local/bin/perl /home/thor/Programs/t
+esting/has-miner-0.1.pl $HAS_break[5] $format $data_type";
        my $proc = Proc::Background->new($command);
        print "Miner Started: ",$proc->pid,"\n" if defined $proc;     
+   
    }
}else{
    print "\nThere are No Messages in the folder: $mailspool\n";
}

$db->disconnect();

exit;

[download]

In reply to DBD::mysql fetchrow_array failed by deadpickle

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