The world rejoiced as [EMAIL PROTECTED] (Martijn van Oosterhout) wrote: > On Fri, May 24, 2002 at 12:43:36PM -0500, Gunther Schadow wrote: >> - Sending a parse tree in XML for processing by the optimizer. >> This circumvents the SQL language and avoids the kinds of >> syntactic ideosyncrasies of SQL (e.g., where you put commas.) >> This is fairly trivial, but of course the question is, would it >> be worth it? X-Mailer: mh-e 6.1; nmh 1.0.4+dev; Emacs 21.4
> I don't know if you can design something in XML that is expressive > and simple enough to compete with SQL. SQL is a simple language, why > replace it with something unless it is demonstrably better. SQL is good at providing "linear" queries; queries that indicate some "linear" relationship between elements. It is not so good at representing hierarchical relationships, which is what XML is about. The SQL: SELECT FIELDS FROM TABLE provides you with a linear list. SQL isn't _nearly_ as nice at representing things that are naturally expressed as trees. It's pretty easy to have a DB schema where you essentially have to submit an SQL query for every level of the tree. And I am not ignoring JOIN here; that adds _some_ ability to join together levels of trees, but not an unlimited ability. The XML model fundamentally involves a hierarchy, and the 'query method' involves passing in a function that reshapes that hierarchy. I think there would be considerable value to that. It certainly needs to be thought about before it is implemented, but it's worth thinking about, to be sure. -- (reverse (concatenate 'string "gro.gultn@" "enworbbc")) http://www.ntlug.org/~cbbrowne/multiplexor.html "It is easier to move a problem around (for example, by moving the problem to a different part of the overall network architecture) than it is to solve it." -- RFC 1925 ---------------------------(end of broadcast)--------------------------- TIP 3: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly
