Re: Expanding HOT updates for expression and partial indexes

On Thu, Feb 19, 2026, at 3:43 PM, Andres Freund wrote:
> Hi,
>
> On 2026-02-17 16:15:02 -0500, Greg Burd wrote:
>> > Why does simple_heap_update() need to do the HeapDetermineColumnsInfo()
>> > inside heap_update()? It seems like you're trying to avoid doing the
>> > same work the executor is doing to determine the modified_attrs bitmap,
>> > but either (a) the work is cheap; or (b) the work to make the bitmap is
>> > expensive.
>>
>> simple_heap_update() is exclusively called during catalog tuple updates and
>> does not involve the executor at all, these are direct calls into heap to
>> store catalog tuples.

Hey Andres,

> Just FYI, there are probably a fair number of extensions using
> simple_heap_update(). That number used to be a lot higher, but I don't think
> there should be a hard assumption about it just being used for catalog updates
> in the code.

Makes sense. These patches don't change simple_heap_update() in any functional way and so extensions should be fine.

> Greetings,
>
> Andres Freund

best.

-greg