Re: Expanding HOT updates for expression and partial indexes

On Mon, 2026-03-16 at 14:35 -0400, Greg Burd wrote:
> Now I want to rename ExecGetAllUpdatedCols() to
> ExecUpdateTargetedCols(), maybe I will.  And while I'm at it I'll
> change the single non-trigger use case in index_unchanged_by_update()
> to my new ExecUpdateTargetedCols() function which better matches that
> use anyway.

Does this mean a new bitmap of "actually changed values" that's a
subset of targeted columns?

If so it feels like quite a few bitmaps and we might need to expand
some comments to explain the subtle meanings of each, and when they are
valid, and what kinds of false positives they might contain (hopefully
none have false negatives).

Also, the "actually changed values" is only valid for a single tuple,
and it would be good to clarify that and make sure there's not a lot of
room for confusion there.

Regards,
    Jeff Davis