Обсуждение: Why does pg_dump set default_with_oids to true?

On Mon, 2009-10-26 at 11:04 -0400, Kynn Jones wrote:
> I've noticed that the dumps generated by pg_dump set the parameter
> default_with_oids to true in various places (separated by setting it
> back to false in-between).
>
>
> This happens even for databases whose creation and maintenance did not
> involve any explicit setting of this parameter.
>
>
> The documentation deprecates setting this variable to true.  Why does
> pg_dump do it?

It is picking up objects that have OIDS.

Joshua D. Drake

>
>
> TIA!
>
>
> Kynn
>
>


--
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Command Prompt, Inc: http://www.commandprompt.com/ - 503.667.4564
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Kynn Jones escribió:
> I've noticed that the dumps generated by pg_dump set the parameter
> default_with_oids to true in various places (separated by setting it back to
> false in-between).
>
> This happens even for databases whose creation and maintenance did not
> involve any explicit setting of this parameter.
>
> The documentation deprecates setting this variable to true.  Why does
> pg_dump do it?

To dump tables that were created WITH OIDS.

--
Alvaro Herrera                                http://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.

Alvaro Herrera <alvherre@commandprompt.com> writes:
> Kynn Jones escribi�:
>> The documentation deprecates setting this variable to true.  Why does
>> pg_dump do it?

> To dump tables that were created WITH OIDS.

What is deprecated is the use of the WITH OIDS feature, not the variable
;-).  But it is not pg_dump's charter to enforce that deprecation.

Maybe what you are asking is why it uses SET default_with_oids rather
than attaching WITH OIDS to the CREATE TABLE commands.  That was done
as a compatibility measure so that the dump files would still be
readable by PG versions that didn't understand WITH OIDS --- they'd
reject the SET commands but still accept the CREATE TABLE commands.
By the same token the files are a shade more portable to other DBMSes
than they would be with WITH OIDS clauses.  Neither of these arguments
is hugely compelling, perhaps, but avoiding the use of a variable isn't
very compelling either ...

            regards, tom lane

On Mon, 2009-10-26 at 11:04 -0400, Kynn Jones wrote:
> I've noticed that the dumps generated by pg_dump set the parameter
> default_with_oids to true in various places (separated by setting it
> back to false in-between).
>
>
> This happens even for databases whose creation and maintenance did not
> involve any explicit setting of this parameter.
>
>
> The documentation deprecates setting this variable to true.  Why does
> pg_dump do it?

It is picking up objects that have OIDS.

Joshua D. Drake

>
>
> TIA!
>
>
> Kynn
>
>


--
PostgreSQL.org Major Contributor
Command Prompt, Inc: http://www.commandprompt.com/ - 503.667.4564
Consulting, Training, Support, Custom Development, Engineering
If the world pushes look it in the eye and GRR. Then push back harder. - Salamander