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* Are these metadata ALTER TABLE commands transactionally safe?
@ 2026-05-14 20:05 Ron Johnson <ronljohnsonjr@gmail.com>
2026-05-14 21:26 ` Re: Are these metadata ALTER TABLE commands transactionally safe? David G. Johnston <david.g.johnston@gmail.com>
0 siblings, 1 reply; 4+ messages in thread
From: Ron Johnson @ 2026-05-14 20:05 UTC (permalink / raw)
To: Pgsql-admin <pgsql-admin@lists.postgresql.org>
PG 17.9
BEGIN;
ALTER TABLE x RENAME TO x_hold;
ALTER TABLE y.x SET SCHEMA a;
ALTER TABLE x OWNER TO foo;
COMMIT;
I don't trust the validity of synthetic tests when Prod is ill-behaved JDBC
connections.
--
Death to <Redacted>, and butter sauce.
Don't boil me, I'm still alive.
<Redacted> lobster!
^ permalink raw reply [nested|flat] 4+ messages in thread
* Re: Are these metadata ALTER TABLE commands transactionally safe?
2026-05-14 20:05 Are these metadata ALTER TABLE commands transactionally safe? Ron Johnson <ronljohnsonjr@gmail.com>
@ 2026-05-14 21:26 ` David G. Johnston <david.g.johnston@gmail.com>
2026-05-15 01:03 ` Re: Are these metadata ALTER TABLE commands transactionally safe? Ron Johnson <ronljohnsonjr@gmail.com>
0 siblings, 1 reply; 4+ messages in thread
From: David G. Johnston @ 2026-05-14 21:26 UTC (permalink / raw)
To: Ron Johnson <ronljohnsonjr@gmail.com>; +Cc: Pgsql-admin <pgsql-admin@lists.postgresql.org>
On Thursday, May 14, 2026, Ron Johnson <ronljohnsonjr@gmail.com> wrote:
> PG 17.9
>
> BEGIN;
> ALTER TABLE x RENAME TO x_hold;
> ALTER TABLE y.x SET SCHEMA a;
> ALTER TABLE x OWNER TO foo;
> COMMIT;
>
>
Define “transactionally safe”.
> I don't trust the validity of synthetic tests when Prod is ill-behaved
> JDBC connections.
>
>
Then do them over a local connection using psql?
David J.
^ permalink raw reply [nested|flat] 4+ messages in thread
* Re: Are these metadata ALTER TABLE commands transactionally safe?
2026-05-14 20:05 Are these metadata ALTER TABLE commands transactionally safe? Ron Johnson <ronljohnsonjr@gmail.com>
2026-05-14 21:26 ` Re: Are these metadata ALTER TABLE commands transactionally safe? David G. Johnston <david.g.johnston@gmail.com>
@ 2026-05-15 01:03 ` Ron Johnson <ronljohnsonjr@gmail.com>
2026-05-15 01:13 ` Re: Are these metadata ALTER TABLE commands transactionally safe? David G. Johnston <david.g.johnston@gmail.com>
0 siblings, 1 reply; 4+ messages in thread
From: Ron Johnson @ 2026-05-15 01:03 UTC (permalink / raw)
To: Pgsql-admin <pgsql-admin@lists.postgresql.org>
On Thu, May 14, 2026 at 5:26 PM David G. Johnston <
david.g.johnston@gmail.com> wrote:
> On Thursday, May 14, 2026, Ron Johnson <ronljohnsonjr@gmail.com> wrote:
>
>> PG 17.9
>>
>> BEGIN;
>> ALTER TABLE x RENAME TO x_hold;
>> ALTER TABLE y.x SET SCHEMA a;
>> ALTER TABLE x OWNER TO foo;
>> COMMIT;
>>
>>
> Define “transactionally safe”.
>
Any open transactions will still see the original tables.
>
>
>> I don't trust the validity of synthetic tests when Prod is ill-behaved
>> JDBC connections.
>>
>>
> Then do them over a local connection using psql?
>
The applications which I don't want to throw errors are ill-behaved JDBC
connections. Sorry for the ambiguity.
--
Death to <Redacted>, and butter sauce.
Don't boil me, I'm still alive.
<Redacted> lobster!
^ permalink raw reply [nested|flat] 4+ messages in thread
* Re: Are these metadata ALTER TABLE commands transactionally safe?
2026-05-14 20:05 Are these metadata ALTER TABLE commands transactionally safe? Ron Johnson <ronljohnsonjr@gmail.com>
2026-05-14 21:26 ` Re: Are these metadata ALTER TABLE commands transactionally safe? David G. Johnston <david.g.johnston@gmail.com>
2026-05-15 01:03 ` Re: Are these metadata ALTER TABLE commands transactionally safe? Ron Johnson <ronljohnsonjr@gmail.com>
@ 2026-05-15 01:13 ` David G. Johnston <david.g.johnston@gmail.com>
0 siblings, 0 replies; 4+ messages in thread
From: David G. Johnston @ 2026-05-15 01:13 UTC (permalink / raw)
To: Ron Johnson <ronljohnsonjr@gmail.com>; +Cc: Pgsql-admin <pgsql-admin@lists.postgresql.org>
On Thursday, May 14, 2026, Ron Johnson <ronljohnsonjr@gmail.com> wrote:
> On Thu, May 14, 2026 at 5:26 PM David G. Johnston <
> david.g.johnston@gmail.com> wrote:
>
>> On Thursday, May 14, 2026, Ron Johnson <ronljohnsonjr@gmail.com> wrote:
>>
>>> PG 17.9
>>>
>>> BEGIN;
>>> ALTER TABLE x RENAME TO x_hold;
>>> ALTER TABLE y.x SET SCHEMA a;
>>> ALTER TABLE x OWNER TO foo;
>>> COMMIT;
>>>
>>>
>> Define “transactionally safe”.
>>
>
> Any open transactions will still see the original tables.
>
>
That would involve locking, most DDL simply won’t happen while open
transactions are using the objects. Normal visibility semantics then apply
beyond that - which depend on isolation level.
David J.
^ permalink raw reply [nested|flat] 4+ messages in thread
end of thread, other threads:[~2026-05-15 01:13 UTC | newest]
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2026-05-14 20:05 Are these metadata ALTER TABLE commands transactionally safe? Ron Johnson <ronljohnsonjr@gmail.com>
2026-05-14 21:26 ` David G. Johnston <david.g.johnston@gmail.com>
2026-05-15 01:03 ` Ron Johnson <ronljohnsonjr@gmail.com>
2026-05-15 01:13 ` David G. Johnston <david.g.johnston@gmail.com>
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