Exist: arrow operator in combination with range index

[merenyics]

What is the problem

The following expressions (which should be interpreted and evaluated identically as far as I know),

$coll//a[contains(., 'str')] => count()

and

count( $coll//a[contains(., 'str')] )

... may, in fact, return different values.

After some investigation I concluded that the difference is due to the fact that element 'a' has a case-insensitive range index defined on it, and the first expression containing the arrow operator fails to use the index, hence the different results.

Similar expressions with a matches(., 'str') filter clause always give identical values.

What did you expect

I expected the two expressions to be evaluated in exactly the same way

Context information

• eXist-db version: 4.3.1
• Java version: Java8u161
• Operating system: Win10
• 64 bit
• How is eXist-db installed? jar
• no custom changes

[duncdrum]

This could be a bug. Can you expand your report a bit so we can reproduce this. We need to know how the index is configured, and a sample query (and data) that shows the different results.

[merenyics]

This may help you reproduce the bug a little easier:

my XML

<debug>
<a>Test</a>
<a>test</a>
</debug>

index config

 <collection xmlns="http://exist-db.org/collection-config/1.0">
     <index xmlns:xs="http://www.w3.org/2001/XMLSchema">
         <range>
             <create qname="a" type="xs:string" case="no"/>
         </range>
     </index>
 </collection>

xquery

xquery version "3.1";
<debug>
    <case nr="1" expected="2" result="{count(doc('debug.xml')//a[contains(.,'test')])}"/>
    <case nr="2" expected="2" result="{(doc('debug.xml')//a[contains(.,'test')])=>count()}"/>
</debug>

and the offending result:

<debug>
    <case nr="1" expected="2" result="2"/>
    <case nr="2" expected="2" result="1"/>
</debug>

[line-o]

Seems to be fixed in 5.3.0 could not be reproduced.
I assume this was fixed by #2470 and #2471