On 2023-Jul-02, Wen Yi wrote:
> Hi community
> When I read the Internals document (41.1. The Query Tree),
> the introduction of the 'the result relation' confuse me.
There are "result relations" in commands that modify a relation, such as
insert or update. The result relation is where the new tuples are
inserted, or where the modified tuples are.
> in my original understand, I guess the use of ResTarget is to store
> the columns of the result, like:
>
> SELECT row_1, row_2 FROM table;
Yeah. Those aren't necessarily in the result relation, because (as the
doc says) a SELECT does not even *have* a result relation.
--
Álvaro Herrera Breisgau, Deutschland — https://www.EnterpriseDB.com/
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