On 2014-06-14 16:44:10 -0400, Tom Lane wrote: > Andres Freund <and...@2ndquadrant.com> writes: > > On 2014-06-14 15:48:52 -0400, Tom Lane wrote: > >> Well, it wouldn't be "unsafe" (barring volatile functions in the UPDATE, > >> which are unsafe already). It might be slow, but that's probably better > >> than failing. > > > I forgot the details, but IIRC it's possible to write a ON UPDATE ... > > DO INSTEAD rule that's safe wrt multiple evaluations today by calling a > > function passing in the old pkey and NEW. At least I believed so at some > > point in the past :P > > Hm. But you might as well use a trigger, no? Is anyone likely to > actually be doing such a thing?
I don't think anybody is likely to do such a thing on an actual table, but INSTEAD OF for views is pretty new. For a long time rules were the the only way to implement updatable views (including any form of row level security). > It's conceivable that we could optimize the special case of NEW.*, > especially if it appears in the rule query's targetlist. But it's > trouble I don't really care to undertake ... I think it's fine to just throw an error. Greetings, Andres Freund -- Andres Freund http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
