Re: Reporting WAL file containing checkpoint's REDO record in pg_controldata's result

On Fri, Mar 23, 2012 at 18:05, Fujii Masao <masao.fujii@gmail.com> wrote:
> On Sat, Mar 24, 2012 at 1:49 AM, Robert Haas <robertmhaas@gmail.com> wrote:
>> On Fri, Mar 23, 2012 at 12:42 PM, Fujii Masao <masao.fujii@gmail.com> wrote:
>>> On Fri, Mar 23, 2012 at 9:41 PM, Robert Haas <robertmhaas@gmail.com> wrote:
>>>> On Fri, Mar 23, 2012 at 6:13 AM, Fujii Masao <masao.fujii@gmail.com> wrote:
>>>>> On Fri, Mar 23, 2012 at 5:56 PM, Magnus Hagander <magnus@hagander.net> wrote:
>>>>>> Might it be a good idea to put it on it's own row instead of changing
>>>>>> the format of an existing row, in order not to break scripts and
>>>>>> programs that are parsing the previous output?
>>>>>
>>>>> Good idea! What row name should we use for the WAL file containing
>>>>> REDO record? "Latest checkpoint's REDO file"?
>>>>
>>>> Sounds good to me.  I like the idea, too.  The status quo is an
>>>> unnecessary nuisance, so this will be a nice usability improvement.
>>>
>>> Attached patch adds new row "Latest checkpoint's REDO WAL segment:" into
>>> the result of pg_controldata. I used the term "WAL segment" for the row name
>>> instead of "file" because "WAL segment" is used in another row "Bytes per WAL
>>> segment:". But better name?
>>
>> s/segment/file/g?
>
> Yep, "file" might be more intuitive for a user than "segment". Attached is the
> "file" version of the patch.

We're already using "file" to mean something different *internally*,
don't we? And since pg_controldata shows fairly internal information,
I'm not sure this is the best idea.

Maybe compromise and call it "segment file" - that is both easier to
understand than segment, and not actually using a term that means
something else...

--
 Magnus Hagander
 Me: http://www.hagander.net/
 Work: http://www.redpill-linpro.com/