Re: [basex-talk] Query optimizer bug with nested for? - java.lang.NullPointerException at Path.index(Path.java:673)

Maybe it's a newbie issue, but I would like your comments.

…definitely something you shouldn't encounter as a newbie either ;) Thanks for reporting it.

Does the exception also occur with the latest snapshot [1]?

Cheers Christian

[1] http://files.basex.org/releases/latest/

I'm writing a RESTXQ method to search among a couple of databases. ( >100 databases )

Some databases are split into a couple of parts due to the number of nodes. For example US: it's separated into US00, US01 and US02.

So, my problem is:

if I replace "*for $usPart in ('US00')*" by "*for $usPart in ('US00','US01',''US02)*" in *QUERY [A]*, I get this error:

*Improper use? Potential bug? Your feedback is welcome:* *Contact: basex-talk@mailman.uni-konstanz.de basex-talk@mailman.uni-konstanz.de* *Version: BaseX 9.3.2* *Java: Oracle Corporation, 1.8.0_251* *OS: Windows 10, amd64* *Stack Trace: * *java.lang.NullPointerException*

• at org.basex.query.expr.path.Path.index(Path.java:673)*
• at org.basex.query.expr.path.Path.optimize(Path.java:157)*
• at org.basex.query.expr.gflwor.For.toPredicate(For.java:220)*
• at org.basex.query.expr.gflwor.GFLWOR.optimizeWhere(GFLWOR.java:532)*
• at org.basex.query.expr.gflwor.GFLWOR.optimize(GFLWOR.java:109)*
• at org.basex.query.expr.gflwor.GFLWOR.compile(GFLWOR.java:100)*
• at org.basex.query.expr.Extension.compile(Extension.java:45)*
• at org.basex.query.expr.SwitchGroup.compile(SwitchGroup.java:40)*
• at org.basex.query.expr.Switch.compile(Switch.java:60)*
• at org.basex.query.expr.gflwor.GFLWOR.compile(GFLWOR.java:96)*
• at org.basex.query.expr.gflwor.ForLet.compile(ForLet.java:43)*
• at org.basex.query.expr.gflwor.GFLWOR.compile(GFLWOR.java:90)*
• at org.basex.query.scope.MainModule.comp(MainModule.java:81)*
• at org.basex.query.QueryCompiler.compile(QueryCompiler.java:114)*
• at org.basex.query.QueryCompiler.compile(QueryCompiler.java:105)*
• at org.basex.query.QueryContext.compile(QueryContext.java:312)*
• at org.basex.query.QueryProcessor.compile(QueryProcessor.java:79)*

Using "*for $usPart in ('US00')*" it works without any problem. With one element there is no problem, with two or more it fails.

Any ideas about what I'm doing wrong?

Here is the *QUERY [A]*

---

declare namespace gb="http://www.ipo.gov.uk/schemas/tm";

let $text:="christian" let $registries:=('GB','US')

let $results := for $registry in $registries return switch ($registry)

       case "US"
       return
       (# db:enforceindex #) {
              for $usPart in ('US00')
              for $tmUS in

db:open($usPart)/trademark-applications-daily/application-information/file-segments/action-keys/case-file where $tmUS/case-file-header/mark-identification/text() contains text {$text} using stemming return <trademark><ipo>US</ipo><text>{$tmUS/case-file-header/mark-identification/text()}</text></trademark> }

       case "GB"
       return
           (# db:enforceindex #) {
               for $tmGB in

db:open('GB')/gb:MarkLicenceeExportList/gb:TradeMark where $tmGB/gb:WordMarkSpecification/gb:MarkVerbalElementText/text() contains text {$text} return <trademark><ipo>GB</ipo><text>{$tmGB/gb:WordMarkSpecification/gb:MarkVerbalElementText/text()}</text></trademark>

            }

        default return ""

return
<result>
    <total>{count($results)}</total>
    <trademarks>
    {
        for $result in $results
        return $result
    }
    </trademarks>
</result>

---

Regards, Sebastian