Re: [HACKERS] WIP: Faster Expression Processing v4

On 3/10/17 14:24, Andres Freund wrote:
> What problem are you thinking of exactly, and what'd be the solution?
> I'd guess that people wouldn't like being unable to change columns in a
> table if some function returned the type.

Well, that's pretty much the problem.

For example:

create type t1 as (a int, b int);
create function f1() returns setof t1 language plpgsql   as $$ begin return query values (1, 2); end $$;
alter type t1 drop attribute b;
select * from f1();  -- fail

The dependency system should arguably guard against that.  Yes, it would
make some things more cumbersome, but, well, it already does that.

>> Not necessarily in this patch, but I would like to keep the options
>> open.
> 
> Yea, seems worth thinking about.  I don't think the patch closes down
> options?

nope

-- 
Peter Eisentraut              http://www.2ndQuadrant.com/
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