With the public Beta 2 of SQL 2005, I have noticed that a lot of arguments have started to surface in the public newsgroups and list servers about Standards, especially the ISO SQL-92, SQL:1999 and SQL:2003 ones (ISO/IEC JTC 1/SC 32/WG 3).
Every vendor implements a portion of the current standard as they see fit. This is not all bad. If they did exactly the same, we would have no need for competing products, and then one that runs on Windows and one that runs on UNIX will suffice.
I've been doing a lot of reading on what the various camps say about the standards and here are a few good links:
It is not possible for a vendor, who releases a product in 2000, to comply to a standard published late 1999. That would be foolish as time does not permit this and the testing would not be thorough enough. SQL 2005 is coming 5 years after SQL 2000, and it does contain more SQL:1999 and SQL:2003 standards compliant features, but still, it is not possible to include them all.
Just because a RDMS does not support one particular feature, does it make it a lemon? No, there are generally enough work-arounds to keep performance and code simplicity to acceptable levels.
All 3 big vendors are missing big portions of the standards in their current shipping and beta products, so use the RDMS that suits the application and stop arguing about little features that the average user does not have on the "must have" list. Most users don't need to latest features, as they are quite often on still on Current minus 1 or minus 2 versions of the vendors product, because the applications they run don't work with the new standards.