Andrew, the big problem is that there are still some areas of significant syntax difference between Postgres and Oracle, and without an Oracle installation to test with people often end up committing broken code. Or they commit code in PG syntax for Oracle and don't realize it. Also, some people have just decided that Oracle support is a nuisance they don't care to be bothered with and so they just don't, with the result that some non-core packages are completely broken for Oracle because they reference queries that are out of date or missing.
Even for those who make the effort to get it right, xql files are a pain in the behind. I have complete sympathy for those who see no value in supporting Oracle and view the overhead of xql files as an unnecessary waste of their time. I have suggested in the past that since we're not likely to support more than two databases, it might make sense to pull all the PG queries back into the Tcl scripts, and only have Oracle queries in their own files.
I really don't know what the solution is. Having separate release tracks for Postgres and Oracle might work, but my gut feeling is that there are not enough Oracle users to keep the Oracle version in usable shape. I can tell you from my recent expeirences with project-manager and photo-album that it can be a *lot* of work to clean up after someone who only supports PG, and I'm not optimistic that there are enough resources out there to keep up with it, especially now that, as Carl said, Sloan is no longer going to be contributing significant funding.
