Re: HOT readme missing documentation on summarizing index handling

On 7/7/23 18:34, Matthias van de Meent wrote:
> On Fri, 7 Jul 2023 at 00:14, Tomas Vondra <tomas.vondra@enterprisedb.com> wrote:
>>
>> Yeah, README.HOT should have been updated, and I see no reason not to
>> backpatch this to v16. Barring objections, I'll do that tomorrow.
>>
>> I have two suggesting regarding the README.HOT changes:
>>
>> 1) I'm not entirely sure it's very clear what "referential integrity of
>> indexes across tuple updates" actually means. I'm afraid "referential
>> integrity" may lead readers to think about foreign keys. Maybe it'd be
>> better to explain this is about having index pointers to the new tuple
>> version, etc.
>>
>> 2) Wouldn't it be good to make it a bit more explicit we now have three
>> "levels" of HOT:
>>
>>   (a) no indexes need update
>>   (b) update only summarizing indexes
>>   (c) update all indexes
>>
>> The original text was really about on/off, and I'm not quite sure the
>> part about "exception" makes this very clear.
> 
> Agreed on both points. Attached an updated version which incorporates
> your points.
> 

Thanks, pushed after correcting a couple typos.


regards

-- 
Tomas Vondra
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