Re: On Scalability

2010/10/7 Simon Riggs <simon(at)2ndquadrant(dot)com>:
> On Thu, 2010-10-07 at 14:10 +0200, Vincenzo Romano wrote:
>
>> Making these things sub-linear (whether not O(log n) or even O(1) ),
>> provided that there's  way to, would make this RDBMS more appealing
>> to enterprises.
>> I mean also partial indexes (as an alternative to table partitioning).
>> Being able to effectively cope with "a dozen child tables or so" it's more
>> like an amateur feature.
>> If you really need partitioning (or just hierarchical stuff) I think you'll need
>> for quite more than a dozen items.
>> If you partition by just weeks, you'll need 50+ a year.
>>
>> Is there any precise direction to where look into the code for it?
>>
>> Is there a way to put this into a wish list?
>
> It's already on the wish list ("TODO") and has been for many years.
>
> We've mostly lacked somebody with the experience and time/funding to
> complete that implementation work. I figure I'll be doing it for 9.2
> now; it may be difficult to do this for next release.
>
> Theoretically, this can be O(n.log n) for range partitioning and O(1)
> for exact value partitioning, though the latter isn't a frequent use
> case.

O(n*log n) is what I would expect from a good algorithm.

> Your conclusion that the current partitioning only works with a dozen or
> so items doesn't match the experience of current users however.

People on the mailing lists says so.
I think I'm forced now to plan for tests on our side, despite this is
not what I'd
like to do with the "most advanced open source database".
I'll publish the results on my blog, anyway.

> --
>  Simon Riggs           www.2ndQuadrant.com
>  PostgreSQL Development, 24x7 Support, Training and Services
>
>

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