xpath where && clause

Question

I have xml data like this

<users>
    <user email="[email protected]">
        <password>pass</password>
        ..
    </user>
</users>

I want to retrieve the user's record (xml format) filtering by email and password. I have tried

for $user in doc("users")/user
               [@email="'.$email.'"]
               [password="'.$password.'"] 
return $user

but I get errors.

Please, how can I retrieve that user's data in xml format so that I can use something like domdocument or simplexmlparser to get the respective nodes?

My reference was http://www.w3schools.com/xsl/xpath_syntax.asp

Answer 1

You would probably want to combine the constrains to one single constraint

for $user in doc("users")//user[@email="'.$email.'" and password="'.$password.'"] return $user

This could also be achieved in one go by:

doc("users")//user[@email="'.$email.'" and password="'.$password.'"]

HTH,

Peter

Answer 2

The most likely cause of the errors you report is that your query asked for user elements that appear as the outermost element of the users document and which satisfy some further constraints, thus:

doc("users")/user[...][...]

But the XML you show has users, not user, as the outermost element.

In the short run, using ...//user instead of .../user, as is done in prker's answer, will solve this problem. (His recommendation to use only a single predicate makes no sense and has nothing to do with whatever problems you had.) The problem can also be fixed by getting the path right: doc("users")/users/user...

In the long run, you should learn to understand what is happening in your XPath expressions. Here, doc("users") returns the document node at the root of the XML document you specify, and the next step, /user (short for /child::user) asks for an element node named user which is the child of the document node.

Answer 3

It worked with this

'for $user in doc("users")//user 
  where 
    $user/password = "'.$password.'" and 
    $user[@email="'.$email.'"] 
  return $user ';

Reference from http://www.w3schools.com/xsl/xquery_intro.asp