Re: how to get XML::LibXML perfect xpath query ?

I don't understand why you don't get same namespace every time

Anyway, If the XML are small and you need access to just a few nodes you could you XML::Simple, for example:

use XML::Simple;
use strict;
use warnings;

my $xml = <<XML;
<?xml version="1.0" standalone="yes"?>
<sdnList>
  <sdnEntry>
   <lastName>Hello world !</lastName>
  </sdnEntry>
</sdnList >
XML

my $xml1 = XMLin($xml);2
my $result = $xml1->{sdnEntry}->{lastName};
print "result:$result\n"; ;

$xml = <<XML;
<?xml version="1.0" standalone="yes"?>
  <sdnList xmlns="http://tempuri.org/sdnList.xsd" >
    <sdnEntry>
      <lastName>Hello world !</lastName>
    </sdnEntry>
</sdnList >
XML

my $xml2 = XMLin($xml);
$result = $xml1->{sdnEntry}->{lastName};
print "result:$result\n";
[download]

I've had performance problems using xpath queries, even it was faster to instantiate the document and consumed less memory than XML::Simple, overall it was slower accessing nodes ( which makes totally sense as XML::Simple returns a hash ).

My point is if you need a simple parser ( i.e: for config files or for consuming small services once a while ) I'd stick to XML::Simple. In environments of high volume or frequent parsing of huge XML documents I would use Expat instead it is really fast.

Comment on Re: how to get XML::LibXML perfect xpath query ? Download Code

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Re^2: how to get XML::LibXML perfect xpath query ? by ikegami (Patriarch) on Jun 13, 2010 at 00:07 UTC
In environments of high volume or frequent parsing of huge XML documents I would use Expat instead it is really fast. In my experience, XML::LibXML is 12x faster than XML::Parser (Expat) at creating the same Perl-land data structure.	[reply]
Re^3: how to get XML::LibXML perfect xpath query ? by bluescreen (Friar) on Jun 13, 2010 at 03:45 UTC
My DOM parser tests compared XML::Simple vs. XML::LibXML in two platforms Solaris 10 and Linux 2.6, all my tests in Solaris ( different documents with different sizes ) showed XML::LibXML was slower than XML::Simple ( It was much slower accessing nodes), as for Linux it was the opposite and XML::LibXML was 8-10x faster than XML::Simple. On the other hand comparing a SAX parser using XML::Parser vs. a DOM parser using XML::LibXML or XML::Simple, expat won in both Solaris and Linux. Honestly, I haven't tried XML::LibXML::SAX and maybe it is way faster than XML::Parser. This link its a bit outdated but It has some benchmarks. Probably things changed notably since then.	[reply]
Re^4: how to get XML::LibXML perfect xpath query ? by ikegami (Patriarch) on Jun 13, 2010 at 03:58 UTC
It was much slower accessing nodes You seem to have missed "at creating the same Perl-land data structure." Visiting every node was included in the benchmark. A task using SOAP::Lite that took two minute was sped up to 15 seconds when I replaced Expat with XML::LibXML as its parser. I kept the change mininal: XML::LibXML was used to create the same data structure that Expat was used to create. Honestly, I haven't tried XML::LibXML::SAX and maybe it is way faster than XML::Parser. As I mentioned, XML::Parser is by far the fastest existing backend for XML::Simple. I'm pretty sure I've posted benchmarks on PerlMonks.	[reply]
Re^2: how to get XML::LibXML perfect xpath query ? by Kanishka.black0 (Scribe) on Jun 13, 2010 at 04:19 UTC
Definately LibXML can handle complex data structures ... and perfomance is done well ... more over LibXML is well maintained .. unlike other's	[reply]