How to manually specify the column names using DBD::CSV? - perl

Question

I am using DBD::CSV to show csv data. Sometimes the file doesn't contain column names, so we have to manually define it. But after I followed the documentation, I got stuck with how to make the attribute skip_first_row work. The code I have is:
#! perl
use strict;
use warnings;
use DBI;
my $dbh = DBI->connect("dbi:CSV:", undef, undef, {
f_dir => ".",
f_ext => ".txt/r",
f_lock => 2,
csv_eol => "\n",
csv_sep_char => "|",
csv_quote_char => '"',
csv_escape_char => '"',
csv_class => "Text::CSV_XS",
csv_null => 1,
csv_tables => {
info => {
file => "countries.txt"
}
},
FetchHashKeyName => "NAME_lc",
}) or die $DBI::errstr;
$dbh->{csv_tables}->{countries} = {
skip_first_row => 0,
col_names => ["a","b","c","d"],
};
my $sth = $dbh->prepare ("select * from countries limit 1");
$sth->execute;
while (my #row = $sth->fetchrow_array) {
print join " ", #row;
print "\n"
}
print join " ", #{$sth->{NAME}};
The countries.txt file is like this:
AF|Afghanistan|A|Asia
AX|"Aland Islands"|E|Europe
AL|Albania|E|Europe
But when I ran this script, it returns
AX Aland Islands E Europe
AF AFGHANISTAN A ASIA
I expected it to either return:
AF AFGHANISTAN A ASIA
a b c d
or
a b c d
a b c d
Does any know what's going on here?

Answer 1

For some reason, contrary to the documentation, it doesn't see the per-table settings unless you pass them to connect.
my $dbh = DBI->connect("dbi:CSV:", undef, undef, {
f_dir => ".",
f_ext => ".txt/r",
f_lock => 2,
csv_eol => "\n",
csv_sep_char => "|",
csv_quote_char => '"',
csv_escape_char => '"',
csv_class => "Text::CSV_XS",
csv_null => 1,
csv_tables => {
countries => {
col_names => [qw( a b c d )],
}
},
FetchHashKeyName => "NAME_lc",
}) or die $DBI::errstr;
Then it works fine:
my $sth = $dbh->prepare ("select * from countries limit 1");
$sth->execute;
print "#{ $sth->{NAME} }\n"; # a b c d
while (my $row = $sth->fetch) {
print "#$row\n"; # AF Afghanistan A Asia
}