Re: Review: listagg aggregate

Marko Tiikkaja <marko.tiikkaja@cs.helsinki.fi>

From: Marko Tiikkaja <marko.tiikkaja@cs.helsinki.fi>

To: Pavel Stehule <pavel.stehule@gmail.com>

Cc: Hitoshi Harada <umi.tanuki@gmail.com>, Robert Haas <robertmhaas@gmail.com>, Takahiro Itagaki <itagaki.takahiro@oss.ntt.co.jp>, "David E. Wheeler" <david@kineticode.com>, "pgsql-hackers@postgresql.org Hackers" <pgsql-hackers@postgresql.org>

Date: 2010-01-28T17:29:04Z

Lists: pgsql-hackers

On 2010-01-28 19:17, Pavel Stehule wrote:
> 2010/1/28 Hitoshi Harada <umi.tanuki@gmail.com>:
>> What about get_fn_expr_arg_stable() to check if the argument is stable
>> during aggregate?
> 
> I newer know so this function exists. Now we can
> 
> a) check and allow only stable params
> b) when second parameter is stable, then store it and use it as constant.
> 
> I prefer a)

Someone might have a perfectly good use case for using different
delimiters.  I don't think it's a good idea to be artificially limiting
what you can and can't do.


Regards,
Marko Tiikkaja