Re: bug report: slow getColumnTypeName

On Wed, Oct 17, 2012 at 12:56 AM, Craig Ringer <ringerc@ringerc.id.au> wrote:
> On 10/17/2012 07:28 AM, Dave Cramer wrote:
>>
>> So what is the consensus on this.
>>
>> I would lean towards removing serial types here
>
>
> I certainly want to, as I think the status quo is not only inefficient and
> incorrect but it fails to even function as designed (incorrectly calling
> 'integer' columns generated by a sequence 'serial' no matter what the
> sequence is) and cannot easily be fixed.
>
> The questions that must still be answered are:
>
> - How do we tell developers about the change?
>
> - Is a compatibility flag required?
>
> - What might it break? Do we need to test popular ORM systems or let
>   their developers know?
>
> - What does the metadata spec actually require us to supply?
>
>
> The 9.2 driver has been pushed and it's a backwards-incompatible change, so
> it's probably a change that's only suitable for 9.3/master. I'm inclined to
> just make the change in master, push a beta driver to the website, and see
> it reports come in. I can test Hibernate and EclipseLink out, but I'm pretty
> sure they won't care.
>
>
> BTW, I'm quite surprised that PostgreSQL doesn't expose information about
> column value generation in INFORMATION_SCHEMA.COLUMNS at the moment; the
> "is_identity" column is always "NO" and "is_generated" is always "NEVER".
> `pg_attribute` doesn't seem to convey it either. Shouldn't we be able to ask
> PostgreSQL for this information?
>
> I'll have a look and see how the driver currently reports whether fields are
> generated, are identity fields, etc.
>
> Looking at the number of issue reports that focus on metadata, I suspect
> that's a real weak point of the current driver and really needs a review.
> Yay. Something for all that abundant spare time.

So I spent some more time on this. This change was made in 2004. Why
is it only a problem now ?

Yes, metadata is the big issue. Postgres just doesn't expose it like
others do. If it were easy the metadata would have been done.

As far as int + default nextval goes, that sort of is the definition
of a serial.

Dave Cramer

dave.cramer(at)credativ(dot)ca
http://www.credativ.ca


>
>
> --
> Craig Ringer
>
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