st 18. 12. 2019 v 21:12 odesÃlatel Merlin Moncure <mmonc...@gmail.com> napsal:
> On Wed, Dec 18, 2019 at 12:38 PM Pavel Stehule <pavel.steh...@gmail.com> > wrote: > > > > Hi > > > > I had a talk with one boy about development in plpgsql. He uses table's > functions. More times he uses returns types based on some table type + few > attributes. Now he use a ugly hack - he create a view on table plus some > columns - and then he use the view related type as table function result > type. For similar uses cases there can be interesting to have a possibility > to create types by extending other types. Probably almost all functionality > is inside now - so it should not be hard work. > > > > My idea is implement inherits clause for CREATE TYPE command. > > > > Some like > > > > CREATE TYPE fx_rt (xx int) INHERITS(pg_class); > > > > What do you think about this idea? > > How about using composition style approaches? > > create type base as (...) > > create type extended as (b base, ...) > > create function foo() returns extended as ... > It is a possibility, but it is not practical, because base type will be nested, it is hard to access to nested fields .. Currently I can do CREATE TABLE base (...); -- instead CREATE TYPE CREATE TABLE extended (...) -- INHERITS (base) CREATE FUNCTION foo() RETURNS SETOF extended AS .. This is working perfect - just disadvantage is garbage table "extended" > merlin >
