If you want to query your XML-file, XPath is the way: And here is an example (I slightly changed your XML-file so all elements have different content): 
use strict;
use XML::XPath;
use XML::XPath::XMLParser;

my $xp = XML::XPath->new( xml => *DATA );

print 'There are ', $xp->find('queries/query')->size, " 'query' nodes.
+\n";
foreach my $element (qw/topN layer filter name datatype/) {
    print "$element: ",
        (
        join ', ',
        map { XML::XPath::XMLParser::as_string($_) =~ />([^<]*)</ }
            $xp->find("queries/query/$element")->get_nodelist
        ),
        "\n";
} ## end foreach my $element (qw/topN layer filter name datatype/)

__DATA__
<?xml version='1.0'?>
<queries>
    <query>
        <name>topHosts 20</name>
        <layer>LINK 20</layer>
        <topN>20</topN>
        <datatype>topHosts 20</datatype>
        <filter></filter>
    </query>
    <query>
        <name>topHosts 120</name>
        <layer>LINK 120</layer>
        <topN>120</topN>
        <datatype>topHosts 120</datatype>
        <filter></filter>
    </query>
</queries>

[download]
Output:
There are 2 'query' nodes.
topN: 20, 120
layer: LINK 20, LINK 120
filter: 
name: topHosts 20, topHosts 120
datatype: topHosts 20, topHosts 120

[download]
And yes I know that the regex to extract the text-data from the nodes is very crude ...

Update: added a code example.

Update2: simplified and shortened code

CountZero

A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James

In reply to Re: XML parsing problem by CountZero
in thread XML parsing problem by avi_2009

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