Reading XML into PHP

I'm trying to determine the best course of action for the display of data for a project I'm working on. My client is currently using a proprietary CMS geared towards managing real estate. It easily lets you add properties, square footage, price, location, etc. The company that runs this CMS provides the data in a pretty straightforward XML file that they say offers access to all of the data my client enters.

I've read up on PHP5's SimpleXML feature and I grasp the basic concepts well enough, but my question is: can I access the XML data in a similar fashion as if I were querying a MySQL database?

For instance, assuming each entry has a unique ID, will I be able to set up a view and display just that record using a URL variable开发者_运维知识库 like: http://example.com/apartment.php?id=14

Can you also display results based on values within strings? I'm thinking a form submit that returns only two bedroom properties in this case.

Sorry in advance if this is a noob question. I'd rather not build a custom CMS for my client if for no other reason than they'd only have to login to one location and update accordingly.

Some short answers on your questions:
a. Yes you can access XML data with queries, but using XPath instead of SQL. XPath is for XML what SQL is for databases, working quite different.
b. Yes you can build a php program that receives an id as parameter and uses this for an XPath search on a given XML file.
c. All data in a XML file is a string, so it is no problem to search for or display strings. Even your example id=14 is to handle as a string.

You might be interested in this further information:
http://www.ibm.com/developerworks/library/x-simplexml.html?S_TACT=105AGX06&S_CMP=LP
http://www.ibm.com/developerworks/library/x-xmlphp1.html?S_TACT=105AGX06&S_CMP=LP

PHP can access XML not only via SimpleXML but also with DOM. SimpleXML accesses the elements like PHP-arrays, DOM provides a w3c-DOM-compatible api.

See php.net for other ways to access XML, but they seem not to be appropriate for you.