Re: Replication slots and footguns

On Thu, Mar 13, 2014 at 8:09 PM, Josh Berkus <josh(at)agliodbs(dot)com> wrote:
> On 03/13/2014 05:01 PM, Robert Haas wrote:
>> On Thu, Mar 13, 2014 at 6:45 PM, Josh Berkus <josh(at)agliodbs(dot)com> wrote:
>>> On 03/13/2014 01:17 PM, Robert Haas wrote:
>>>> I think "in use" is just as clear as active, and I think the text
>>>> Andres proposed previously reads a whole lot more nicely than this:
>>>>
>>>> replication slot "%s" is in use by another backend
>>>
>>> Then we should change the column name in the pg_stat_replication_slots
>>> view to "in_use". My point is that the error message and the diagnostic
>>> view should use the same word, or we're needlessly confusing our users.
>>
>> I see. That's an interesting point....
>
> As I said earlier, the fact that the current error message says "active"
> and the column in pg_stat_replication_slots is called "active" meant I
> knew *immediately* where to look. So I'm speaking from personal experience.

Well we may have kind of hosed ourselves, because the in-memory data
structures that represent the data structure have an in_use flag that
indicates whether the structure is allocated at all, and then an
active flag that indicates whether some backend is using it. I never
liked that naming much. Maybe we should go through and let in_use ->
allocated and active -> in_use.

--
Robert Haas
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