See the other thread. Good points.
ANSI SQL is a LOT later than Oracle's
implementation. Therefore, I don't see
why Oracle has to follow it if they think
they got a better solution: after all, ANSI
*is* a committee...
--
Cheers
Nuno Souto
wizofoz2k_at_yahoo.com.au.nospam
"Stu Charlton" <stuartc_at_mac.com> wrote in message
news:21398ab6.0403311801.1e0e1edd_at_posting.google.com...
>
> I agreed with you up until this one, sorry. There are some subtle
> aspects to Oracle's versioning mechanism that makes its SERIALIZABLE
> isolation level unlike other databases' SERIALIZABLE isolation levels,
> so it is most definitely *NOT* transparent.
>
> This is not because Oracle is deficient; it is because ANSI SQL's
> isolation definitions are ambiguous and inadequate. Oracle's
> SERIALIAZBLE level is different in that it makes a "non-serial"
> history possible (this is called "write skew" , i.e. Tom Kyte's
> example in his expert one-on-one book). This usually is an "OK" thing
> in practise as long as you're aware of it; the benefits outweigh this
> anomaly usually. A form of phantom write is also sometimes possible.
>
Received on Thu Apr 01 2004 - 06:57:08 CST
