Re: Index maintenance function for BRIN doesn't check RecoveryInProgress()

On 13 June 2018 at 15:51, Alvaro Herrera <alvherre(at)2ndquadrant(dot)com> wrote:
> On 2018-Jun-13, Alexander Korotkov wrote:
>
>> On Wed, Jun 13, 2018 at 12:48 PM Kuntal Ghosh
>> <kuntalghosh(dot)2007(at)gmail(dot)com> wrote:
>> > On Wed, Jun 13, 2018 at 2:28 PM, Masahiko Sawada <sawada(dot)mshk(at)gmail(dot)com> wrote:
>> > > Hi,
>> > >
>> > > Three functions: brin_summarize_new_values, brin_summarize_range and
>> > > brin_desummarize_range can be called during recovery as follows.
>> > >
>> > > =# select brin_summarize_new_values('a_idx');
>> > > ERROR: cannot acquire lock mode ShareUpdateExclusiveLock on database
>> > > objects while recovery is in progress
>> > > HINT: Only RowExclusiveLock or less can be acquired on database
>> > > objects during recovery.
>
> Good catch!
>
>> > > I think we should complaint "recovery is in progress" error in this
>> > > case rather than erroring due to lock modes.
>> > +1
>>
>> +1,
>> but current behavior doesn't seem to be bug, but rather not precise
>> enough error reporting. So, I think we shouldn't consider
>> backpatching this.
>
> I guess you could go either way ... we're just changing one unhelpful
> error with a better one: there is no change in behavior. I would
> backpatch this, myself, and avoid the code divergence.

WAL control functions all say the same thing, so we can do that here also.

I'd prefer it if the message was more generic, so remove the
summarization/desummarization wording from the message. i.e.
"BRIN control functions cannot be executed during recovery"

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Simon Riggs http://www.2ndQuadrant.com/
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