Re: Review observations for partial REFRESH MATERIALIZED VIEW patc

On 5/19/26 7:42 AM, vellaipandiyan sm wrote:
> I reviewed the REFRESH MATERIALIZED VIEW ... WHERE patch and had a few 
> questions around concurrency semantics.
> 
>   * The original DELETE -> INSERT approach exposing a consistency gap
>     makes sense, especially once tuple locks disappear after DELETE. The
>     newer FOR UPDATE + single-CTE approach seems safer, though I wonder
>     whether overlapping refreshes could still encounter deadlock
>     scenarios around UPSERT conflicts.
>   * The CONCURRENTLY behavior also feels somewhat unintuitive here. With
>     WHERE refreshes, the non-CONCURRENT path appears more permissive for
>     writers than CONCURRENTLY WHERE, which seems opposite to the
>     expectation established by normal REFRESH MATERIALIZED VIEW semantics.
>   * It may also help to document the intended guarantees around
>     overlapping partial refreshes and concurrent DML on base tables.

Hi,

Thanks for the review, but please reply-all to the original thread when 
you review a patch so the original author and previous reviewers can see 
your review.

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-- 
Andreas Karlsson
Percona