Re: transforms

Peter,

> There is also a {Perl, Python, Ruby, etc.} binding for {libpq, libmysql,
> libpng, libyaml, libssl, libgmp, etc.}, each as a separately
> downloadable and buildable package. I don't think anyone has ever
> seriously considered a system by which if, say, you have Python and
> libyaml installed, pyyaml magically appears. Might be nice, but maybe
> not. The solution, in practice, is that you download pyyaml, and it
> pulls in any required dependencies. This would work the same way.

That would be good too, although we don't currently have that
capability; if I try to install hstore_plpython without plpython
installed, it just errors out. Aside from that, what can we reasonably
do for 9.3 to get this feature in?

Maybe we add a transforms/ subdirectory of contrib, so that it can be as
crowded as we want? Or put the transforms on PGXN for now?

I want to see this feature go in so that the community starts writing
transforms this year instead of next year.

BTW, dependancies seem to be working OK for DROP:

postgres=# drop extension plpythonu;
ERROR: cannot drop extension plpythonu because other objects depend on it
DETAIL: extension hstore_plpythonu depends on extension plpythonu
function look_up_hstore(hstore,text) depends on transform for hstore
language plpythonu
extension ltree_plpythonu depends on extension plpythonu
HINT: Use DROP ... CASCADE to drop the dependent objects too.
STATEMENT: drop extension plpythonu;
ERROR: cannot drop extension plpythonu because other objects depend on it
DETAIL: extension hstore_plpythonu depends on extension plpythonu
function look_up_hstore(hstore,text) depends on transform for hstore
language plpythonu
extension ltree_plpythonu depends on extension plpythonu
HINT: Use DROP ... CASCADE to drop the dependent objects too.

--
Josh Berkus
PostgreSQL Experts Inc.
http://pgexperts.com