Alvaro Herrera wrote: > On Sun, Jun 20, 2004 at 04:37:16PM -0400, Tom Lane wrote: > > Alvaro Herrera <[EMAIL PROTECTED]> writes: > > > Here I present the nested transactions patch and the phantom Xids patch > > > that goes with it. > > > > I looked at the phantom XIDs stuff a bit. I still have little confidence > > that the concept is correct :-( but here are some comments on the code > > level. > > Ok. I for one think this got much more complex than I had originally > thought it would be. I agree the changes to Set/Get Xmin/Xmax are way > beyond what one would want, but the alternative would be to spread the > complexity into their callers and I think that would be much worse. > > I don't have a lot of confidence in this either. The patch will be > available in archives if anybody wants to implement this in a cleaner > and safer way; I'll continue working on the rest of the things you > pointed out in the subtransactions patch.
I am sorry to have given Alvaro another idea that didn't work. However, thinking of options, I wonder if instead of phantom xids, we should do phantom cids. Because only the local backend looks at the command counter (cid). I think it might be alot cleaner. The phantom cid would have a tuple bit set indicating that instead of being a cid, it is an index into an array of cmin/cmax pairs. -- Bruce Momjian | http://candle.pha.pa.us [EMAIL PROTECTED] | (610) 359-1001 + If your life is a hard drive, | 13 Roberts Road + Christ can be your backup. | Newtown Square, Pennsylvania 19073 ---------------------------(end of broadcast)--------------------------- TIP 5: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faqs/FAQ.html
