Re: Declarative partitioning - another take

On Tue, Dec 20, 2016 at 9:14 PM, Amit Langote
<Langote_Amit_f8(at)lab(dot)ntt(dot)co(dot)jp> wrote:
> On 2016/12/21 1:45, Alvaro Herrera wrote:
>> Robert Haas wrote:
>>> On Tue, Dec 20, 2016 at 10:27 AM, Alvaro Herrera
>>> <alvherre(at)2ndquadrant(dot)com> wrote:
>>>> Even if we decide to keep the message, I think it's not very good
>>>> wording anyhow; as a translator I disliked it on sight. Instead of
>>>> "skipping scan to validate" I would use "skipping validation scan",
>>>> except that it's not clear what it is we're validating. Mentioning
>>>> partition constraint in errcontext() doesn't like a great solution, but
>>>> I can't think of anything better.
>>>
>>> Maybe something like: partition constraint for table \"%s\" is implied
>>> by existing constraints
>>
>> Actually, shouldn't we emit a message if we *don't* skip the check?
>
> Scanning (aka, not skipping) to validate the partition constraint is the
> default behavior, so a user would be expecting it anyway, IOW, need not be
> informed of it. But when ATExecAttachPartition's efforts to avoid the
> scan by comparing the partition constraint against existing constraints
> (which the user most probably deliberately added just for this) succeed,
> that seems like a better piece of information to provide the user with,
> IMHO. But then again, having a message printed before a potentially long
> validation scan seems like something a user would like to see, to know
> what it is that is going to take so long. Hmm.
>
> Anyway, what would the opposite of Robert's suggested message look like:
> "scanning table \"%s\" to validate partition constraint"?

Maybe: partition constraint for table \"%s\" is implied by existing constraints

--
Robert Haas
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