EvanCarroll has asked for the wisdom of the Perl Monks concerning the following question:

I'm 99.9% sure this is a bug in DBD::CSV please corroborate! I've spent now 4hrs tracking this down, <notice> this is as compact as I could get it.</notice> This thing is absolutely driving me crazy. 
#!/usr/bin/perl
use strict;
no warnings;
use DBD::CSV;
my $file = shift;
my $dbh = DBI->connect('DBI:CSV:f_dir=.')
  or die "Cannot connect $!";
$dbh->{'csv_tables'}{'current_table'}
  = { file => $file, quote_char => '~', eol=> "\r\n" };
my $sth = $dbh->prepare(q{SELECT * FROM current_table});
$sth->execute();
while ( defined ( my @row = $sth->fetchrow_array ) ) {
  if ( $sth->errstr() ) { print $sth->errstr() and die };
}

print $sth->errstr();

[download]
And it seems to crash on this data: 
~Style ID~,~Hist Style ID~,~Model ID~,~Model Year~,~Sequence~,~Style C
+ode~,~Full Style Code~,~Style Name~,~True Base Price~,~Invoice~
282198,     2007700803    ,16139     ,2007        ,1         ,~ZMB67~ 
+    ,~ZMB67~          ,~2dr Conv~  ,~Y~              ,21319.80

[download]

(program run with ./program file.csv)
Error Message as follows: 
DBD::CSV::st fetchrow_array failed: Attempt to fetch row from a Non-SE
+LECT statement [for Statement "SELEC                                 
+                T * FROM current_table"] at ./col_proc.pl line 12.
Died at ./col_proc.pl line 12.
evan@dealermade:/var/chrome/NVDv2_US_EN$ ./col_proc.pl ./problem.txt
DBD::CSV::st fetchrow_array failed: Attempt to fetch row from a Non-SE
+LECT statement [for Statement "SELECT * FROM current_table"] at ./col
+_proc.pl line 12.
Died at ./col_proc.pl line 12.

[download]

As a last note, the whitespace in the csv are to show that there is no real funny business going on there. Thanks in advance monks. From a later post.
From a later post: synopsis of thread. BUG FOUND When this is the data file it works fine!!! Data File: 
~Style Name~
~5dr Crew Cab 130~

[download]
Deduction: The bug is DBD::CSV breaking if there is an occurance of a double quotes within a non-standard quote character of '~', (so what is the point of using quote_char) ?
Still no resolution


Evan Carroll
www.EvanCarroll.com

Replies are listed 'Best First'.
Re: A bug in DBD::CSV?
by diotalevi (Canon) on Apr 12, 2006 at 22:37 UTC

    It appears you're checking errstr more often than you should. Your code works just fine if you just test the results of the fetches. I'm sure that if a result came back undefined or empty you'd want to check errstr then. This sounds like doing die $! if $! which fails for the exact same reason - if you haven't just done a system operation then you don't know that $! will be false.

    In preference to doing manual testing of of success/failure, it's much easier to ask DBI to throw exceptions for you: DBI->connect( 'DBI:CSV:f_dir=.', undef, undef,{ RaiseError => 1, ShowErrorStatement => 1 } ).

    ⠤⠤ ⠙⠊⠕⠞⠁⠇⠑⠧⠊

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      The problem isn't just the error, The error is the symptom of the problem. I was altered to this because the rows below this problem were not read at all. I will supply more details tomorrow.


      Evan Carroll
      www.EvanCarroll.com
[reply]

        I copied your exact code and data into files. It worked great as long as I didn't check for the failure text when there wasn't a failure.

        ⠤⠤ ⠙⠊⠕⠞⠁⠇⠑⠧⠊

[reply]
Re: A bug in DBD::CSV?
by cosimo (Hermit) on Apr 13, 2006 at 13:00 UTC

    Hi Evan,
    Change: 

    while( defined ( my @row = $sth->fetchrow_array ) ) {

    [download]
    to: 
    while( my @row = $sth->fetchrow_array ) {

    [download]
    and an endless loop problem is fixed.
    I think the other problem is your peculiar choice of quote_char.
    I found that specifying the general quote char on DBI connection options makes the error go away. As you probably know, this is a general setting, not per table/csv handle. 
    my $dbh = DBI->connect('DBI:CSV:f_dir=.;csv_quote_char=~;')  or die ..
+.

    [download]
    I didn't have time to investigate on this one, though it would be interesting to do.
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Re: A bug in DBD::CSV?
by EvanCarroll (Chaplain) on Apr 13, 2006 at 16:23 UTC

    EASIER BUG DEMONSTRATION

    Perl Script 
    #!/usr/bin/perl
use strict;
no warnings;
use DBI;
my $file = shift;
my $dbh = DBI->connect('DBI:CSV:f_dir=.;')
  or die "Cannot connect $!";
$dbh->{'csv_tables'}{'current_table'}
  = { file => $file, quote_char => '~' };
my $sth = $dbh->prepare(q{SELECT * FROM current_table});
$sth->execute();
while ( my @row = $sth->fetchrow_array ) {
  print @row;
  print "\n";
}

    [download]


    Data File: 
    ~Style Name~
~5dr Crew Cab 130" WB 2WD LS~

    [download]
    BUG FOUND When this is the data file it works fine!!!
    Data File: 
    ~Style Name~
~5dr Crew Cab 130~

    [download]
    Deduction: The bug is DBD::CSV breaking if there is an occurance of a double quotes within a non-standard quote character of '~', (so what is the point of using quote_char) ?


    Evan Carroll
    www.EvanCarroll.com
[reply]
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