problem on xml parsing with xml::Simple module

sarf13 has asked for the wisdom of the Perl Monks concerning the following question:

Hi monks I am using XML::Simple module for parsing my attached xml data. I wrote mentioned code for fetching query data value. It is working fine. But it is giving this error “Can't use string ("GENERATE EXPRESS STATIST") as a HASH ref while "strict refs" in use” .i think this error because of “foreach my $sql ($query->{content}) {” loop on line no 42. Can you suggest some way solve this??

Thank you very much

PERL Script

#!/usr/bin/perl 

use strict;
use warnings;

use Data::Dumper;
use SQLValidation;
use XML::Simple;


my $xml_obj1 =  XML::Simple->new();

#my $file_path     = 'C:\Users\Desktop\sql_test.xml' ;
my $file_path     = 'C:\Users\Desktop\derived_tif_cd.XML' ;
my $xmlfile       = $xml_obj1->XMLin($file_path) or die "Failed for $f
+ile_path: $!";

#print Dumper $xmlfile;
=c
my $val = $xmlfile->{queries}->{query}->[2]->{content};
print "$val";
=cut
foreach my $queries ($xmlfile->{queries}){
    if($xmlfile->{queries} eq 'query') {
        foreach my $query (@{$queries->{query}}) 
        {
            foreach my $sql ($query->{content}) {
                    print "$sql\n";
                }
        }
    }
    else {
        foreach my $query (@{$queries->{query}}) {
            print "---->$query\n";
        }
    }
}
[download]

XML Data File

<Common_Checks>
        <comments>
                This xml includes validations for order event types (C
+hecks for Others).
        </comments>
        <queries>
        <comments>
            ORDER_TYPE_CODE and expiration date for TIF  code derivati
+on:
        </comments>
        <query>
        
                     INSERT INTO table_name   (column1, column2, colum
+n3,...) select (value1, value2, value3,...);    
                
                <orderTypes>order_nw_stgng</orderTypes>
                <orderTypes>order_or_stgng</orderTypes>
                <orderTypes>order_oe_stgng</orderTypes>
                <orderTypes>order_cr_stgng</orderTypes>
                
                <queryParam>BATCH_ID</queryParam>
            </query>
            
            <query>
                   GENERATE EXPRESS STATISTICS ON drvd_tif_order_stgng
+;
            </query>

        <comments>
            ORDER_TYPE_CODE and expiration date for TIF  code derivati
+on:
        </comments>
        <query>
            
            INSERT INTO table_name   (column1, column2, column3,...) s
+elect (value1, value2, value3,...);   
                        
                <orderTypes>order_nw_stgng</orderTypes>
                <orderTypes>order_or_stgng</orderTypes>
                <orderTypes>order_oe_stgng</orderTypes>
                <orderTypes>order_cr_stgng</orderTypes>
                
                <queryParam>BATCH_ID</queryParam>
    
        </query>  
            
       <query>
            GENERATE EXPRESS STATISTICS ON drvd_tif_order_stgng;
           </query>
            
        
                
        </queries>
</Common_Checks>
[download]

Comment on problem on xml parsing with xml::Simple module Select or Download Code

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Re: problem on xml parsing with xml::Simple module by tobyink (Canon) on Aug 07, 2012 at 12:18 UTC
The problem is that XML::Simple's default settings are too clever for their own good. It will sometimes represent your `<query>` elements as a hashref (i.e. when the element has any attributes or child elements) and sometimes treat it as a string. Changing the XML::Simple `ForceContent` setting (switching it on) should solve this, but it will probably cause other issues to pop up instead. My personal recommendation is to switch from XML::Simple to a better XML library. There is a "sweet spot" where things like XML::Simple are awesome, but in my experience it's quite a small sweet spot, and once you're outside that sweet spot it actually becomes much easier to use a more powerful XML library. `use 5.010; use strict; use warnings; use XML::LibXML 1.70; use Text::Trim 'trim'; my $xml = XML::LibXML->load_xml(location => 'C:\Users\Desktop\derived_ +tif_cd.XML'); foreach my $query ($xml->findnodes('//queries/query')) { # Join together the content within the <query> element # but filter out child elements. Just want text. my $sql = join q(), grep { $_->isa('XML::LibXML::Text') } $query->childNodes; say trim($sql); }` [download] `perl -E'sub Monkey::do{say$_,for@_,do{($monkey=[caller(0)]->[3])=~s{::}{ }and$monkey}}"Monkey say"->Monkey::do'`	[reply] [d/l] [select]

Replies are listed 'Best First'.

Re: problem on xml parsing with xml::Simple module
by tobyink (Canon) on Aug 07, 2012 at 12:18 UTC

The problem is that XML::Simple's default settings are too clever for their own good. It will sometimes represent your <query> elements as a hashref (i.e. when the element has any attributes or child elements) and sometimes treat it as a string.

Changing the XML::Simple ForceContent setting (switching it on) should solve this, but it will probably cause other issues to pop up instead.

My personal recommendation is to switch from XML::Simple to a better XML library. There is a "sweet spot" where things like XML::Simple are awesome, but in my experience it's quite a small sweet spot, and once you're outside that sweet spot it actually becomes much easier to use a more powerful XML library.

use 5.010;
use strict;
use warnings;

use XML::LibXML 1.70;
use Text::Trim 'trim';

my $xml = XML::LibXML->load_xml(location => 'C:\Users\Desktop\derived_
+tif_cd.XML');

foreach my $query ($xml->findnodes('//queries/query'))
{
    # Join together the content within the <query> element
    # but filter out child elements. Just want text.
    my $sql = join q(),
        grep { $_->isa('XML::LibXML::Text') }
        $query->childNodes;
        
    say trim($sql);
}
[download]

perl -E'sub Monkey::do{say$_,for@_,do{($monkey=[caller(0)]->[3])=~s{::}{ }and$monkey}}"Monkey say"->Monkey::do'

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