Dear Josh and Andrew, Thanks for the prompt replies. For now it's just a paper. It was Rob and Pim's mission to find out if the SQL /XML standard can be implemented using the postgresql extension mechanism. Building it into the parser was no option.
Best, Djoerd. On Thu, 18 Aug 2005, Andrew Dunstan wrote: > > IIRC, Peter Eisentraut noted a while ago that implementing the SQL/XML > functions properly would require building them into the postgresql > parser as special cases. That of course would mean we wouldn't be using > the extension mechanism, and is something we should normally shy away > from, but I think it could be contemplated for something that is in the > standard. > > The paper does not seem to have addressed the issue of how this could be > done other than bu using the extension mechanism - that seems a bit of a > pity, although maybe that's exactly the topic they were set. > > cheers > > andrew > > Josh Berkus wrote: > > >Paul, Rob, > > > >I just read with some interest your paper on XML queries with PostgreSQL. > >I'm particularly puzzled by some of your conclusions, and thought you might > >want to discuss them with the PGSQL-Hackers mailing list. > > > >Particulary: > >Functions should be able to have a variable amount of arguments. > > > >I find this conclusion odd, because function overloading (that is, the idea > >that a function is defined by the combination of its name and the number and > >type of arguments) is now enshrined in the SQL2003 standard. Of course, > >I wouldn't be at all surprised to find out that the SQL committee had broken > >their own standard. ;-) > > > >Re-defining AS would, as you notice, break many things. However, you could > >easily get around this through quoting. While that would not be exactly > >adherent to the standard, it's easier that re-writing the parser. > > > >In some ways, it seems to me that SQL/XML might be better defined as a > >separate interface to the database; that is, it's own "shell" which is > >incompatible with SQL (since the committee seems to have deliberately made it > >incompatible). > > > >Thoughts? > > > > > > > ---------------------------(end of broadcast)--------------------------- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match