Обсуждение: [HACKERS] Improve logical decoding error message (was wal_level > WAL_LEVEL_LOGICAL)
[HACKERS] Improve logical decoding error message (was wal_level > WAL_LEVEL_LOGICAL)
От
Neha Khatri
Дата:
On Mon, May 22, 2017 at 11:08 PM, Neha Khatri <nehakhatri5@gmail.com> wrote:
As per my understabding, current postgres server supports only three
values for wal_level i.e. 'minimal' , 'replica' or 'logical'. But
following error message brought to notice that there are various code
spots that try to look for wal_level >= WAL_LEVEL_LOGICAL:
select * from pg_create_logical_replication_slot('regression_slot',
'test_decoding');
ERROR: logical decoding requires wal_level >= logical
The Logical Decoding example in the documentation says:
"Before you can use logical decoding, you must set wal_level to
logical and max_replication_slots to at least 1."But above error message is not exactly consistent with this documentation. Would it make sense to keep the error message and the documentation consistent like the attached.
Regards,
Neha
Neha
Вложения
Re: [HACKERS] Improve logical decoding error message (was wal_level > WAL_LEVEL_LOGICAL)
От
Michael Paquier
Дата:
On Tue, May 23, 2017 at 8:08 AM, Neha Khatri <nehakhatri5@gmail.com> wrote: > The Logical Decoding example in the documentation says: > > "Before you can use logical decoding, you must set wal_level to logical > and max_replication_slots to at least 1." > > But above error message is not exactly consistent with this documentation. > Would it make sense to keep the error message and the documentation > consistent like the attached. There is no wal_level higher than logical, so the current sense looks perfectly fine to me. -- Michael
On Tue, May 23, 2017 at 10:26 AM, Michael Paquier <michael.paquier@gmail.com> wrote:
On Tue, May 23, 2017 at 8:08 AM, Neha Khatri <nehakhatri5@gmail.com> wrote:
> The Logical Decoding example in the documentation says:
>
> "Before you can use logical decoding, you must set wal_level to logical
> and max_replication_slots to at least 1."
>
> But above error message is not exactly consistent with this documentation.
> Would it make sense to keep the error message and the documentation
> consistent like the attached.
There is no wal_level higher than logical, so the current sense looks
perfectly fine to me.
If there is no wal_level higher than logical, should the following error message indicate to set it >= logical.
select * from pg_create_logical_replication_slot('regression_slot','test_decoding');
ERROR: logical decoding requires wal_level >= logical
Regards,
Neha
Re: [HACKERS] Improve logical decoding error message (was wal_level> WAL_LEVEL_LOGICAL)
От
Alvaro Herrera
Дата:
Neha Khatri wrote:
> On Tue, May 23, 2017 at 10:26 AM, Michael Paquier <michael.paquier@gmail.com
> > There is no wal_level higher than logical, so the current sense looks
> > perfectly fine to me.
>
> If there is no wal_level higher than logical, should the following error
> message indicate to set it >= logical.
>
> select * from
> pg_create_logical_replication_slot('regression_slot','test_decoding');
> ERROR: logical decoding requires wal_level >= logical
I think it's purposefully ambiguous to cover a possible future
extension.
--
Álvaro Herrera https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
On Tue, 23 May 2017 at 10:55 am, Alvaro Herrera <alvherre@2ndquadrant.com> wrote:
Neha Khatri wrote:
> On Tue, May 23, 2017 at 10:26 AM, Michael Paquier <michael.paquier@gmail.com
> > There is no wal_level higher than logical, so the current sense looks
> > perfectly fine to me.
>
> If there is no wal_level higher than logical, should the following error
> message indicate to set it >= logical.
>
> select * from
> pg_create_logical_replication_slot('regression_slot','test_decoding');
> ERROR: logical decoding requires wal_level >= logical
I think it's purposefully ambiguous to cover a possible future
extension.
Should documentation also have similar statement and indicate future possibility.
What is the benefit of having it just in error message.
Regards,
Neha
--
Cheers,
Neha
Neha
Re: [HACKERS] Improve logical decoding error message (was wal_level> WAL_LEVEL_LOGICAL)
От
Andres Freund
Дата:
On 2017-05-23 10:49:54 +0000, Neha Khatri wrote:
> On Tue, 23 May 2017 at 10:55 am, Alvaro Herrera <alvherre@2ndquadrant.com>
> wrote:
>
> > Neha Khatri wrote:
> > > On Tue, May 23, 2017 at 10:26 AM, Michael Paquier <
> > michael.paquier@gmail.com
> >
> > > > There is no wal_level higher than logical, so the current sense looks
> > > > perfectly fine to me.
> > >
> > > If there is no wal_level higher than logical, should the following error
> > > message indicate to set it >= logical.
> > >
> > > select * from
> > > pg_create_logical_replication_slot('regression_slot','test_decoding');
> > > ERROR: logical decoding requires wal_level >= logical
> >
> > I think it's purposefully ambiguous to cover a possible future
> > extension.
Right, IIRC that's how this notion started.
> Should documentation also have similar statement and indicate future
> possibility.
>
> What is the benefit of having it just in error message.
I personally wouldn't do anything here, it doesn't seem an issue.
- Andres