Re: TABLESAMPLE patch

On 01/04/15 17:52, Robert Haas wrote:
> On Wed, Apr 1, 2015 at 9:49 AM, Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
>> I am still not sure whether it is okay to move REPEATABLE from
>> unreserved to other category. In-fact last weekend I have spent some
>> time to see the exact reason for shift/reduce errors and tried some ways
>> but didn't find a way to get away with the same. Now I am planning to
>> spend some more time on the same probably in next few days and then
>> still if I cannot find a way, I will share my findings and then once
>> re-review
>> the changes made by Petr in last version. I think overall the patch is in
>> good shape now although I haven't looked into DDL support part of the
>> patch which I thought could be done in a separate patch as well.
>
> That seems like a legitimate concern. We usually try not to make
> keywords more reserved in PostgreSQL than they are in the SQL
> standard, and REPEATABLE is apparently non-reserved there:
>
> http://www.postgresql.org/docs/devel/static/sql-keywords-appendix.html
>
> This also makes "method" an unreserved keyword, which I'm not wild
> about either. Adding new keyword doesn't cost *much*, but is this
> SQL-mandated syntax or something we created? If the latter, can we
> find something to call it that doesn't require new keywords?
>

REPEATABLE is mandated by standard. I did try for quite some time to
make it unreserved but was not successful (I can only make it unreserved
if I make it mandatory but that's not a solution). I haven't been in
fact even able to find out what it actually conflicts with...

METHOD is something I added. I guess we could find a way to name this
differently if we really tried. The reason why I picked METHOD was that
I already added the same unreserved keyword in the sequence AMs patch
and in that one any other name does not really make sense.

--
Petr Jelinek http://www.2ndQuadrant.com/
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