I'm trying to find some good Java open source XML databases that have a pluggable persistence layer - can work with a file system (more of an NXD) using its own storage, or for higher data volume requirements can work atop an RDBMS.
They key thing is, we have a bunch of XML documents (XML strings) that we want to be able to execute XPath and XQL statements against. For smaller implementations, we want a lightweight NXD implementation w/o RDBMS. For larger implementations. we want the XML database layer to be able to work against tables with CLOB columns storing the XML strings.
TIA