Re: ALTER TABLE ADD COLUMN fast default

On Tue, Feb 13, 2018 at 6:28 PM, Andrew Dunstan
<andrew.dunstan@2ndquadrant.com> wrote:
> On Fri, Feb 9, 2018 at 3:54 PM, Andrew Dunstan
> <andrew.dunstan@2ndquadrant.com> wrote:
>> On Mon, Feb 5, 2018 at 7:49 AM, Andrew Dunstan
>> <andrew.dunstan@2ndquadrant.com> wrote:
>>> On Mon, Feb 5, 2018 at 7:19 AM, Thomas Munro
>>> <thomas.munro@enterprisedb.com> wrote:
>>>> On Fri, Jan 26, 2018 at 1:23 PM, Andrew Dunstan
>>>> <andrew.dunstan@2ndquadrant.com> wrote:
>>>>> Yeah, thanks. revised patch attached
>>>>
>>>> FYI the identity regression test started failing recently with this
>>>> patch applied (maybe due to commit
>>>> 533c5d8bddf0feb1785b3da17c0d17feeaac76d8?)
>>>>
>>>
>>> Thanks. Probably the same bug Tomas Vondra found a few days ago. I'm on it.
>>>
>>
>>
>> Here's a version that fixes the above issue and also the issue with
>> VACUUM that Tomas Vondra reported. I'm still working on the issue with
>> aggregates that Tomas also reported.
>>
>
> This version fixes that issue. Thanks to Tomas for his help in finding
> where the problem was. There are now no outstanding issues that I'm
> aware of.
>


The attached version largely fixes with the performance degradation
that Tomas Vondra reported, replacing an O(N^2) piece of code in
slot_getmissingattrs() by one that is O(N).

cheers

andrew



-- 
Andrew Dunstan                https://www.2ndQuadrant.com
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