Re: Adding support for Default partition in partitioning

On 2017/04/25 5:16, Robert Haas wrote:
> On Mon, Apr 24, 2017 at 8:14 AM, Ashutosh Bapat
> <ashutosh(dot)bapat(at)enterprisedb(dot)com> wrote:
>> On Mon, Apr 24, 2017 at 4:24 PM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>>> On Mon, Apr 24, 2017 at 5:10 AM, Rahila Syed <rahilasyed90(at)gmail(dot)com> wrote:
>>>> Following can also be considered as it specifies more clearly that the
>>>> partition holds default values.
>>>>
>>>> CREATE TABLE ...PARTITION OF...FOR VALUES DEFAULT;
>>>
>>> The partition doesn't contain default values; it is itself a default.
>>
>> Is CREATE TABLE ... DEFAULT PARTITION OF ... feasible? That sounds more natural.
>
> I suspect it could be done as of now, but I'm a little worried that it
> might create grammar conflicts in the future as we extend the syntax
> further. If we use CREATE TABLE ... PARTITION OF .. DEFAULT, then the
> word DEFAULT appears in the same position where we'd normally have FOR
> VALUES, and so the parser will definitely be able to figure out what's
> going on. When it gets to that position, it will see FOR or it will
> see DEFAULT, and all is clear. OTOH, if we use CREATE TABLE ...
> DEFAULT PARTITION OF ..., then we have action at a distance: whether
> or not the word DEFAULT is present before PARTITION affects which
> tokens are legal after the parent table name. bison isn't always very
> smart about that kind of thing. No particular dangers come to mind at
> the moment, but it makes me nervous anyway.

+1 to CREATE TABLE .. PARTITION OF .. DEFAULT

Thanks,
Amit