These are 2 completely different things:
- XQL and QL are two of many (and I mean
_many_)
proposals to W3C for XML query languages: languages to
query XML documents (which could be flat files but
more likely stored in an XML data base). The result
of a query is a list of documents or fragments of
documents. As long as you stay within a single document
XML::XPath
is probably your best choice, it implements XPath, a
query language limited to a single document, and
DOM-style transformation. BTW as far as I know both
XML::QL and XML::XQL are also limited to searching a
single document, but that's an implementation choice,
not a design choice as for XML::XPath.
- what you are describing is a way to include data from
a relational data base into an XML document. You put
special XML tags in your document and a piece of
software later replaces those tags by the appropriate
data, properly tagged. If you want to import the
result of XML queries into a document you can have a
look at DBIx::XML_RDB, couple it with XML::PYX,
or any other XML processing module, and you can get what you seem to describe
fairly easily. It will probably be a little slower
to write and slower to run than what Oracle offers
but it will be much more portable.
Just don't confuse XML query languages and embedding SQL
statement into an XML document.