Wow!

By the way, if you remove the second brackets, the query works:

SELECT 1 WHERE ('') = '_㉸^'

It requires Java 17, and InterSystems IRIS Enterprise (it uses many connections).

Do I understand correctly that with the built-in Community Edition license, the SQLancer tool cannot be fully used?

One of the options for Caché 2018.1:

set xmlStream=##class(%Stream.FileBinary).%New()
set xmlStream.Filename="C:\test_from.xml"

set jsonStream=##class(%Stream.FileBinary).%New()
set jsonStream.Filename="C:\test_to.json"

#dim d As %Document.Object = ##class(%Document.Object).XML(xmlStream)

do d.%ToJSONStream(.jsonStream)

do jsonStream.%Save()

For i = 1:1:maxRow {
Set cel = pySheet.cell(i,y)
If cel."is_date" {
  Set val = cel.value.date().isoformat() ; ODBC Date
  Set MolDatum = $zdh(val,3) ; LOGICAL Date
  Write $zd(MolDatum),! ; DISPLAY Date
}
}