2010/9/16 Mark Kirkwood <mark.kirkwood@catalyst.net.nz>:
> On 16/09/10 14:05, Robert Haas wrote:
>>
>> On Wed, Sep 15, 2010 at 9:22 PM, Tom Lane<tgl@sss.pgh.pa.us> wrote:
>>
>>>
>>> Hitoshi Harada<umi.tanuki@gmail.com> writes:
>>>
>>>>
>>>> 2010/9/16 Robert Haas<robertmhaas@gmail.com>:
>>>>
>>>>>
>>>>> Oh, key-value store, I bet. Yeah, that would be cool.
>>>>>
>>>
>>>
>>>>
>>>> That's it. Like Redis, Tokyo Cabinet, or something.
>>>>
>>>
>>> What exactly do those get you that an ordinary index, or at worst an
>>> index-organized table, doesn't get you?
>>>
>>
>> For example, you can imagine that if
>> you have a "sessions" table where you store a record for each
>> currently-logged-in user, an unlogged table would be fine. If the
>> database crashes and comes back up again, everyone has to log in
>> again, but that's a rare event and not a disaster if it happens.
>>
>>
>
> Or perhaps even a "sessions" type table where the rows are overwritten in
> place in some manner, to avoid bloat.
>
My answer is "variety". If an index-organized table was the one best
solution, there would not been so many KVSes these days.
Regards,
--
Hitoshi Harada