XDMP-ELEMRIDXNOTFOUND: cts:element-values -- No element range index in MarkLogic 10 [marklogic]

I am new to MarkLogic.

I have XML doc

<?xml  version="1.0" encoding="UTF-8"?>
<books xmlns="http://www.marklogic.com/ns/gs-books">
<book bookid="2">
<title>A Quick Path to an Application</title>
<author>
<last>Smith</last>
<first>James</first>
</author>
<publisher>Scribblers Press</publisher>
<isbn>1494-3930392-4</isbn>
<abstract>
          This book describes in detail the power of how 
          to use Java to build powerful web applications 
          that are built on the MarkLogic Server platform.
      </abstract>
</book>
</books>

How can I use cts:element-values against it?

Here is my try: cts:element-values(xs:QName("test"),"test")

It gives me this error:

[1.0-ml] XDMP-ELEMRIDXNOTFOUND: cts:element-values(fn:QName("","t"), "t") -- No element range index for t collation=http://marklogic.com/collation/ coordinate-system=wgs84 [marklogic]

Solution

In order to be able to use cts:element-values(), the element needs to have a corresponding range-index to use.

Returns values from the specified element value lexicon(s). Value lexicons are implemented using range indexes; consequently this function requires an element range index for each element specified in the function. If there is not a range index configured for each of the specified elements, an exception is thrown.

So, in order to be able to run: cts:element-values(xs:QName("test"),"test")

You would first need to create a String range index for the "test" element (and ensure the reindexer is enabled, and allow for it to finish reindexing the docs with that element, in order to build the lexicon).

You can configure an element-range-index in the Admin UI, programmatically with admin:database-add-range-element-index(), and if you have an ml-gradle project they can be added to the database configuration.