Re: proposal: psql: show current user in prompt

út 4. 4. 2023 v 21:11 odesílatel Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com>
napsal:

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> út 4. 4. 2023 v 20:50 odesílatel Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com>
> napsal:
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>> út 4. 4. 2023 v 19:55 odesílatel Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> napsal:
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>>> Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com> writes:
>>> > út 4. 4. 2023 v 18:42 odesílatel Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> napsal:
>>> >> Basically, I want to reject this on the grounds that it's not
>>> >> useful enough to justify the overhead of marking the "role" GUC
>>> >> as GUC_REPORT. The problems with it not going to work properly
>>> >> with old servers are an additional reason not to like it.
>>>
>>> > If I understand to next comment correctly, the overhead should not be
>>> too
>>> > big
>>>
>>> Yeah, but how big is the use-case? The reason I'm skeptical is that
>>> half the time what you're going to get is "none":
>>>
>>> $ psql
>>> psql (16devel)
>>> Type "help" for help.
>>>
>>> regression=# show role;
>>> role
>>> ------
>>> none
>>> (1 row)
>>>
>>> That's required by SQL spec I believe, but that doesn't make it useful
>>> data to keep in one's prompt.
>>>
>>
>> Who needs it, and who uses different roles, then very quickly uses SET
>> ROLE TO command.
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>> But I fully agree so current behavior can be a little bit messy. I like
>> this feature, and I think it can have some benefits. Proposed
>> implementation is minimalistic.
>>
>> One hard problem is translation of the oid of current_user to name. It
>> requires an opened transaction, and then it cannot be postponed to the end
>> of the statement. On the other hand, when the change of role is done inside
>> a nested command, then it should not be visible from the client side.
>>
>> Can you accept the introduction of a new invisible GUC, that can be
>> modified only by SET ROLE TO command when it is executed as top command?
>>
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> It was stupid idea.
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> There can be implemented fallbacks. When the role is "none", then the
> :USER can be displayed instead.
>
> It can work, because the custom role "none" is not allowed
>
> (2023-04-04 21:10:25) postgres=# create role none;
> ERROR: role name "none" is reserved
> LINE 1: create role none;
>
> ?
>
>
attached updated patch

Regards

Pavel

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>> Regards
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>> Pavel
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>>>
>>> regards, tom lane
>>>
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