On 9/3/07, Alvaro Herrera <[EMAIL PROTECTED]> wrote: > Marko Kreen escribió: > > On 9/3/07, Alvaro Herrera <[EMAIL PROTECTED]> wrote: > > > Florian G. Pflug wrote: > > > > Since we didn't really reach an agreement on how xid_age should behave, > > > > I've reverted it back to the original version. So with this patch, > > > > xid_age will just force assignment of a xid. > > > > > > Is this really a good idea? I'm repeating myself, but a query like > > > > > > select age(xmin) from bigtable > > > > > > could accelerate Xid wraparound. If the server is running close to the > > > limit it could cause a shutdown to prevent the actual wraparound. > > > > Such query would take only one xid, which should not be a problem? > > My guess is that it would execute age(xid) once per tuple? Even if all > the tuples had the same xmin, there's no cache therefore it would > consume as many Xids as there are tuples. > > Am I missing something?
First age() assigns CurrentXid, rest reuse it. -- marko ---------------------------(end of broadcast)--------------------------- TIP 4: Have you searched our list archives? http://archives.postgresql.org