Hi experts,

I am new in Perl and DBI - I have been following book:

O'reilly - Programming Perl DBI - From the ...

I cannot deal with chapter:

2.5.1 The Perl Data::Dumper Module

I rewrote the code and I try to run it with my text-db xxx.txt : $name="MyName";$location="MyLoc";$mapRef="MyRef";$type="MyType";$description="MyDesc";

My code:

#!/usr/bin/perl
use Data::Dumper;

$Data::Dumper::Indent = 0;
$Data::Dumper::Useqq = 1;

$Data::Dumper::Purity = 1;
    
die "Usage: updatemegadata <data file> <site name> <new map reference>
+\n"
unless @ARGV == 3;

my $megalithFile = $ARGV[0];
my $siteName = $ARGV[1];
my $siteMapRef = $ARGV[2];
my $tempFile = "tmp.$$";

open MEGADATA, "<$megalithFile" or die "Can't open $megalithFile: $!\n
+";

open TMPMEGADATA, ">$tempFile" or die "Can't open temporary file $temp
+File: $!\n";

while ( <MEGADATA> ) {

    next unless m/\Q$siteName/;

    my $fields;
    eval $_;
    die if $@;

    my ( $name, $location, $mapref, $type, $description ) = @$fields;

    next unless $siteName eq $name;

    $fields = [ $name, $location, $siteMapRef, $type, $description ];

    $_ = Data::Dumper->new( [ $fields ], [ 'fields' ] )->Dump();
    $_ .= "\n";

} continue {
    print TMPMEGADATA $_ or die "Error writing $tempFile: $!\n";
}
close MEGADATA;

close TMPMEGADATA or die "Error closing $tempFile: $!\n";

unlink $megalithFile or die "Can't delete old $megalithFile: $!\n";

rename $tempFile, $megalithFile or die "Can't rename '$tempFile' to '$
+megalithFile': $!\n";
exit 0;

[download]
It gives no effects after:

perl myScript.pl xxx.txt MyName Lalala

Could you help me? Probably format of my file-db is wrong...

In reply to Cannot update record in file with Dump module by perlisok

Title:
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