Re: NULLs: theoretical problems?
Date: Sat, 18 Aug 2007 21:01:15 +0200 (CEST)
"Brian Selzer" <brian_at_selzer-software.com> wrote in
>> The full 92/2003 standard compliance does require that deferrable
>> constraints should be implemented. The entry/intermediate compliance
>> level does not. There is no notion of "Core SQL" in the standard.
> FYI: I pulled "feature outside Core SQL" from the heading of Table 32
> in ISO/IEC 9075-2:1999 and Table 35 in ISO/IEC 9075-2:2003.
Yes, you are quite right, I was under impression that they had preseved the entry/intermediate/full level taxonomy in '2003 but instead they use 'Core' and 'outside Core' terminology. Sorry about that.
It is odd though that they consider features that are indispensable for any modern SQL based imlementation as not 'core'. For example,
alter table drop column/alter table add constraint/drop constraint isolation level other than serializable (this one is especially funny !) derived table ( select * from (select abc from t1) x)
etc... Received on Sat Aug 18 2007 - 21:01:15 CEST