On Tue, Feb 8, 2011 at 9:48 PM, Tom Lane <t...@sss.pgh.pa.us> wrote: > Robert Haas <robertmh...@gmail.com> writes: >> ... And you could even allow multiple objects: >> ALTER EXTENSION extension_name ADD object-description [, ...]; >> Which might be handy. > > I just thought of a different way of coming at the question, which might > help us make a choice. > > Like ALTER THING SET SCHEMA, ALTER THING SET EXTENSION is implicitly > assuming that there can be only one owning extension for an object.
I would assume that we would enforce that constraint anyway. No? Otherwise when you drop one of the two extensions, what happens to the object? Seems necessary for sanity. > Furthermore, it's not really intended for *removal* of an object from an > extension (a concept that doesn't even exist for SET SCHEMA). We could > take a page from COMMENT ON and use "SET EXTENSION NULL" for that, but > that's surely more of a hack than anything else. True. > In contrast, ALTER EXTENSION ADD doesn't presuppose that you couldn't > add the object to multiple extensions; and it has a natural inverse, > ALTER EXTENSION DROP. I am not necessarily suggesting that we will ever > allow either of those things, but I do suggest that we should pick a > syntax that doesn't look like it's being forced to conform if we ever > want to do it. The DROP case at least seems like it might be wanted > in the relatively near future. Yep. > So that looks to me like a fairly good argument for the ADD syntax. OK by me. There's also the operator class stuff, as a parallel. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
