XPATH 1.0 - How to get all childen elements that exist for one type of parent element

Question

I have this type of XML file :

<Product>
  <item1>...</item1>
  <item2>...</item2>
  <item3>...</item3>
</Product>
<Product>
  <item1>...</item1>
  <item2>...</item2>
  <item4>...</item4>
  <item5>...</item5>
</Product>
<Product>
  <item1>...</item1>
  <item6>...</item6>
</Product>

I would like to get the list of all unique children element of the parent type "Product", like this :

<item1>...</item1>
<item2>...</item2>
<item3>...</item3>
<item4>...</item4>
<item5>...</item5>
<item6>...</item6>

I don't care of what is under these "item" elements, I just want to list all types of "item" elements that can exist under all "Product" elements of my file, using XPATH 1.0 if possible. I want to display each "item" element one time only, even if they exist under several "Product" elements.

How can I do that ? Thank you for your help !

This [SO answer](https://stackoverflow.com/a/11107209/1377895) seems to explain the XPath 1.0 way of listing distinct values — Roman Vottner, Jul 19 '17 at 15:42

zx485 · Answer 1 · 2017-07-19T15:08:10.743

0

This XSLT-1.0 approach matches all children of Product elements and filters them by checking if a node with the same name/local-name has already occured in the preceding-axis.

<xsl:template match="//Product/*">
  <xsl:variable name="this" select="local-name()" />
  <xsl:if test="count(preceding::*[local-name()=$this]) = 0">
    Unique node: <xsl:value-of select="name()"/>
  </xsl:if>
</xsl:template>

edited Jul 19 '17 at 15:08

answered Jul 19 '17 at 15:01

zx485

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derloopkat · Accepted Answer · 2017-07-19T16:13:03.603

0

Using xpath version 1.0, this returns all elements without duplicates.

//Product/*[not(../preceding-sibling::Product/*/local-name()=local-name())]

Using xpath version 2.0 , returns all values without duplicates.

distinct-values(//Product/*/local-name())

edited Jul 19 '17 at 16:13

answered Jul 19 '17 at 15:34

derloopkat

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Do you know any free XML Tool which can run Xpath 2.0 queries ? I'm currently using XML Explorer ; it's quite good but only supports Xpath 1.0 :( – JCD70 Jul 19 '17 at 15:44
I have updated my answer following the suggestion made by Roman Vottner. According to https://www.w3.org/TR/xpath/ *preceding-sibling* should be supported by version 1. In the other hand once I've used Saxon open source implementation with .Net. See https://stackoverflow.com/questions/1525299/xpath-and-xslt-2-0-for-net – derloopkat Jul 19 '17 at 16:06
Xpath v1.0 code does not seem to work, but Xpath v2.0 does. I have managed to use it with Saxon HE command line application. Thank you ! – JCD70 Jul 20 '17 at 08:40

XPATH 1.0 - How to get all childen elements that exist for one type of parent element

2 Answers2