need basic help - listing suggestions

hello,
i am very new to XML and am confused by the way i should list some info.

I have a tree that flows like this:

<AllArticles>
<CompanyName>Name</CompanyName>
<ArticleCount>1</ArticleCount>
<rArticlesPath>
<![CDATA[ActLib]]>
</rArticlesPath>
<Categories>
<Category>
<CategoryName>Cat 1</CategoryName>
<CategoryID>107</CategoryID>
<Articles>
<Article>
<ArticleID>416</ArticleID>
<JobNumber>416-1</JobNumber>
<Subject>
<![CDATA[416 title]]>
</Subject>
<OriginalFile>
<![CDATA[ST 8-3]]>
</OriginalFile>
<ArticleSorts>
<Material>sugar</Material>
<Material>sand</Material>
<Industry>Food</Industry>
<MachineType>Single Deck</MachineType>
</ArticleSorts>
<Materials>
<Material>sugar</Material>
<Material>sand</Material>
</Materials>
<Industries>
<Industry>Food</Industry>
</Industries>
<MachineTypes>
<MachineType>Single Deck</MachineType>
</MachineTypes>
</Article>
</Articles>
</Category>
</Categories>
</AllArticles>



I need to be able to add a varying amount of Materials, Industries, and Machine Types to each Article. How shoudl the structure be set up to accomidate this? I have it in two ways right now that i am testing:

<ArticleSorts>
<Material>sugar</Material>
<Material>sand</Material>
<Industry>Food</Industry>
<MachineType>Single Deck</MachineType>
</ArticleSorts>

<Materials>
<Material>sugar</Material>
<Material>sand</Material>
</Materials>
<Industries>
<Industry>Food</Industry>
</Industries>
<MachineTypes>
<MachineType>Single Deck</MachineType>
</MachineTypes>

I cant seem to understand which of these ways is correct.

Also, I will need to be able to choose the articles later by sorting them by the different elements (Machine Type, Industries, etc..) and the variable passed to them (Material = sand, etc..)

I hope this makes sense.

I am using PHP.

thank you for any guidance.

I think i know you: but anyway.
The second way that you have it is better.


or you could do something like



personally i think the first is the better way to go though. but whatever wat you are more comfortable with.