Re: WIP patch for Todo Item : Provide fallback_application_name in contrib/pgbench, oid2name, and dblink

On Wed, Jun 27, 2012 at 9:57 PM, Shigeru HANADA
<shigeru(dot)hanada(at)gmail(dot)com> wrote:
> On Thu, Jun 14, 2012 at 10:55 PM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>> On Wed, Jun 13, 2012 at 12:07 AM, Amit Kapila <amit(dot)kapila(at)huawei(dot)com> wrote:
>>> To achieve the same in dblink, we need to parse the passed connection string
>>> and check if it contains fallback_application_name, if yes then its okay,
>>> otherwise we need to append fallback_application_name in connection string.
>>
>> That seems undesirable.  I don't think this is important enough to be
>> worth reparsing the connection string for.  I'd just forget about
>> doing it for dblink if there's no cheaper way.
>
> Indeed reparsing connection string is not cheap, but dblink does it for
> checking password requirement for non-in dblink_connstr_check when the
> local user was not a superuser.  So Amit's idea doesn't seem
> unreasonable to me, if we can avoid extra PQconninfoParse call.
>
> Just an idea, but how about pushing fallback_application_name handling
> into dblink_connstr_check?  We reparse connection string unless local
> user was a superuser, so it would not be serious overhead in most cases.
>  Although it might require changes in DBLINK_GET_CONN macro...

*shrug*

If it can be done without costing anything meaningful, I don't object,
but I would humbly suggest that this is not hugely important one way
or the other. application_name is primarily a monitoring convenience,
so it's not hugely important to have it set anyway, and
fallback_application_name is only going to apply in cases where the
user doesn't care enough to bother setting application_name. Let's
not knock ourselves out to solve a problem that may not be that
important to begin with.

--
Robert Haas
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