Re: [HACKERS] Grouping Sets: Fix unrecognized node type bug

On Sat, Jul 18, 2015 at 12:27 AM, Andrew Gierth <andrew(at)tao11(dot)riddles(dot)org(dot)uk
> wrote:

> >>>>> "Kyotaro" == Kyotaro HORIGUCHI <horiguchi(dot)kyotaro(at)lab(dot)ntt(dot)co(dot)jp>
> writes:
>
> Kyotaro> Hello, this looks to be a kind of thinko. The attached patch
> Kyotaro> fixes it.
>
> No, that's still wrong. Just knowing that there is a List is not enough
> to tell whether to concat it or append it.
>
> Jeevan's original patch tries to get around this by making the RowExpr
> case wrap another List around its result (which is then removed by the
> concat), but this is the wrong approach too because it breaks nested
> RowExprs (which isn't valid syntax in the spec, because the spec allows
> only column references in GROUP BY, not arbitrary expressions, but which
> we have no reason not to support).
>
> Attached is the current version of my fix (with Jeevan's regression
> tests plus one of mine).
>

Looks good to me.

>
> --
> Andrew (irc:RhodiumToad)
>
>

--
Jeevan B Chalke
Principal Software Engineer, Product Development
EnterpriseDB Corporation
The Enterprise PostgreSQL Company