[bind10-dev] initial ideas on the "difference" design

[Danny Mayer]

On 10/17/2011 2:33 PM, JINMEI Tatuya / $B?@L at C#:H(B wrote:
> At Sun, 16 Oct 2011 09:12:44 -0400,
> Danny Mayer <mayer at ntp.org> wrote:
> 
>>>> select * from diffs where
>>>> zone_id = Z and
>>>> id >= (select id from diffs where
>>>>    zone_id = Z and version = B and operation = 0
>>>>    order by id asc limit 1)
>>>> order by id asc
>>>
>>> You're right that we can still safely use 'version = B', although your
>>> revised example is getting more complicated, more closer to my
>>> original example in complexity:-)
>>>
>>> But again, this level of details don't have to be fixed right now.  We
>>> can start with any workable one and then upgrade it as we see the need
>>> for it.
>>
>> If you add a timestamp to the diffs table then you can handle the
>> rollover. You can have a table that maps the SOA value to the timestamp
>> whenever it changes and then your diff table just needs the timestamp.
> 
> This essentially seems to be the same as the monotonically increasing
> ID numbers...I'm not sure how the timestamp approach better solves the
> issue.

Timestamps don't rollover. Moreover by using timestamps you know exactly
when a record changed.

Danny