Re: Patch to add a primary key using an existing index - Mailing list pgsql-hackers

On 12/3/10 12:27 PM, Robert Haas wrote:
> On Fri, Dec 3, 2010 at 2:56 PM, r t <pgsql@xzilla.net> wrote:
>> What exactly was the objection to the following -->
>> ALTER TABLE table_name ADD PRIMARY KEY (column_list) USING index_name;
>> Is the objection that you might have been trying to specify a constraint
>> named "using" ? I'm willing to make that option more difficult. :-)
> 
> I think it's that someone might expect the word after USING to be the
> name of an index AM.

Seems unlikely to cause confusion to me.

However, I don't see why we need (column_list). Surely the index has a
column list already?

ALTER TABLE table_name ADD CONSTRAINT pk_name PRIMARY KEY USING index_name

... seems like the syntax most consistent with the existing commands.
Anything else would be confusingly inconsistent with the way you add a
brand-new PK.

--                                  -- Josh Berkus                                    PostgreSQL Experts Inc.
                        http://www.pgexperts.com