Home:Learn XQuery: XQuery Tips and Tricks:Variables in XPath

Can I use variables in my XPath expressions?

If we run the following XQuery:

let $xml := <root><book>book1</book><video>video1</video></root>
for $el in ("book", "video")
return $xml/$el/text()

... we get this error:

It is a type error if the result of a step (other than the last step) in a path expression contains an atomic value.

The problem is that $el is being inserted in the XPath expression as a string literal, not as the name of an element; it as if you tried to run an XPath expression like $xml/”book”/text().

What you typically are trying to do is:

let $xml := <root><book>book1</book><video>video1</video></root>
for $el in ("book", "video")
return $xml/*[local-name() eq $el]/text()

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