Storing / retrieving parts of an xml document with mysql, php, and simpleXML

I'm taking an xml document down from a partner API and I'd like to store the separate nodes into a mysql database so I can rebuild it with specific nodes. I absolutely do not want to parse out the complete document into the database as all I care about are the IDs and the individual nodes in total.

So for example:

<list>
<child>20-30 grandchildren</child>
<child></child>
<child></child>
...
<child></child>
</list>

I'd like to be able to put the blocks into a mysql database and then restore them. That's where I'm falling down: I use simple_xml to get the node and I use REPLACE to add it as a text, but I'm not sure how to them restore it back to . For an array, I'd serialize and than unserialize but that fails here.

Is there an obvious method I'm missing?

You serialize SimpleXMLElement objects to XML with asXML() then you can load the document normally with simplexml_load_string()

You cannot serialize SimpleXMLElement with serialize(), it will not work as expected.