On Wed, 2025-02-26 at 18:08 +0800, Tender Wang wrote:
> Recently, I found Greenplum implement pull-up NOT IN subquery.
> They have the below comments in their codes:
>
> We normalize NOT subqueries using the following axioms:
> *
> * val NOT IN (subq) => val <> ALL (subq)
That is true, but I don't see how it leads to an anti-join
without further consideration. Perhaps you mean something
else by "pull up"...
Yours,
Laurenz Albe
