Re: [REVIEW] pg_last_xact_insert_timestamp

On Mon, Oct 3, 2011 at 6:31 PM, Fujii Masao <masao(dot)fujii(at)gmail(dot)com> wrote:
>> Also, in pg_last_xact_insert_timestamp, the errhint() seems a little
>> strange - this is not exactly a WAL *control* function, is it?
>
> Not only "control" but also "WAL" might be confusing. What about
> "transaction information functions"?

Attached is the updated version of the patch. In the patch, I used the
function name itself in the HINT message, i.e., the HINT message is
the following.

pg_last_xact_insert_timestamp() cannot be executed during recovery.

>> In the documentation, for the short description of
>> pg_last_xact_insert_timestamp(), how about something like "returns the
>> time at which a transaction commit or transaction about record was
>> last inserted into the transaction log"?  Or maybe that's too long.
>> But the current description doesn't seem to do much other than
>> recapitulate the function name, so I'm wondering if we can do any
>> better than that.
>
> Agreed. I will change the description per your suggestion.

Done.

>> I think that instead of hacking up the backend-status copying code to
>> have a mode where it copies everything, you should just have a
>> special-purpose function that computes the value you need directly off
>> the backend status entries themselves.  This approach seems like it
>> both clutters the code and adds lots of extra data copying.
>
> Agreed. Will change.

Done.

Regards,

--
Fujii Masao
NIPPON TELEGRAPH AND TELEPHONE CORPORATION
NTT Open Source Software Center