Re: Slow count(*) again...

On Wed, Oct 13, 2010 at 1:59 PM, Jesper Krogh <jesper(at)krogh(dot)cc> wrote:
> On 2010-10-13 15:28, Robert Haas wrote:
>>
>> On Wed, Oct 13, 2010 at 6:16 AM, Neil Whelchel<neil(dot)whelchel(at)gmail(dot)com>
>>  wrote:
>>
>>>
>>> I might go as far as to rattle the cage of the developers to see if it
>>> makes
>>> any sense to add some column oriented storage capability to Postgres.
>>> That
>>> would be the hot ticket to be able to specify an attribute on a column so
>>> that
>>> the back end could shadow or store a column in a column oriented table so
>>> aggregate functions could work on them with good efficiency, or is that
>>> an
>>> INDEX?
>>>
>>
>> I'd love to work on that, but without funding it's tough to find the
>> time.  It's a big project.
>>
>
> Is it hugely different from just getting the visibillity map suitable
> for doing index-only scans and extracting values from the index
> directly as Heikki has explained?]

I think that there's a lot more to a real column-oriented database
than index-only scans, although, of course, index-only scans are very
important.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company