On Fri, 9 Sep 2005, Tom Lane wrote: > Stephan Szabo <[EMAIL PROTECTED]> writes: > > Is there a case other than a before trigger updating a row we will want to > > act upon later in the statement where we'll get a row with xmax of our > > transaction and cmax greater than the current command? > > The greater-cmax case could occur via any kind of function, not only a > trigger, ie > > update tab set x = foo(x) where ... > > where foo() is a volatile function that internally updates the tab > table.
I *thought* I was missing a case, I just couldn't figure out what. > I suppose you could say that this is horrible programming practice and > anyone who tries it deserves whatever weird behavior ensues ... but > it's not the case that every such situation involves a trigger. Well, the change I was thinking of would have made it an error if foo(x) updated a row that was then later selected by the update rather than the current behavior which I think would have ignored the already updated row, so that's probably not going to work. ---------------------------(end of broadcast)--------------------------- TIP 3: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq