Re: Add column if not exists (CINE)

Поиск
Список
Период
Сортировка
От Robert Haas
Тема Re: Add column if not exists (CINE)
Дата
Msg-id AANLkTim4ti3OxVCNNTFSs+U_swPqTuppzjsgVDAH-k1G@mail.gmail.com
обсуждение исходный текст
Ответ на Add column if not exists (CINE)  (Kjell Rune Skaaraas <kjella79@yahoo.no>)
Список pgsql-hackers
On Wed, Jul 21, 2010 at 2:53 PM, Bernd Helmle <mailings@oopsware.de> wrote:
>
>
> --On 1. Mai 2010 23:09:23 -0400 Robert Haas <robertmhaas@gmail.com> wrote:
>
>> On Wed, Apr 28, 2010 at 9:15 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>>>>
>>>> CREATE OR REPLACE is indeed much more complicated.  In fact, for
>>>> tables, I maintain that you'll need to link with -ldwim to make it
>>>> work properly.
>>>
>>> This may in fact be an appropriate way to handle the case for tables,
>>> given the complexity of their definitions.
>>
>> Patch attached.
>
> I had an initial look at Robert's patch. Patch applies cleanly,
> documentation and regression tests included, everything works as expected.
> When looking at the functionality there's one thing that strikes me a
> little:
>
> bernd@localhost:bernd #*= CREATE TABLE IF NOT EXISTS foo(id int);
> ERROR:  duplicate key value violates unique constraint
> "pg_type_typname_nsp_index"
> DETAIL:  Key (typname, typnamespace)=(foo, 2200) already exists.
>
> This is what you get from concurrent CINE commands. The typname thingie
> might be confusing by unexperienced users, but i think its hard to do
> anything about it ?

I get the same error message from concurrent CREATE TABLE commands
even without CINE...

S1:
rhaas=# begin;
BEGIN
rhaas=# create table foo (id int);
CREATE TABLE

S2:
rhaas=# begin;
BEGIN
rhaas=# create table foo (id int);
<blocks>

S1:
rhaas=# commit;
COMMIT

S2:
ERROR:  duplicate key value violates unique constraint
"pg_type_typname_nsp_index"
DETAIL:  Key (typname, typnamespace)=(foo, 2200) already exists.

I agree it would be nice to fix this.  I'm not sure how hard it is.  I
don't think it's the job of this patch.  :-)

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise Postgres Company


В списке pgsql-hackers по дате отправления:

Предыдущее
От: Dimitri Fontaine
Дата:
Сообщение: Re: managing git disk space usage
Следующее
От: Andrew Dunstan
Дата:
Сообщение: Re: git config user.email