Hello!
Is there any non-functional difference between these two forms of Update?
WITH name AS ( SELECT )
UPDATE tbl SET ...
FROM name
WHERE tbl.id = name.id
and
UPDATE tbl SET ...
FROM ( WITH qry AS ( SELECT ) SELECT * FROM qry ) AS name
WHERE tbl.id = name.id
They both better give the same results but does the backend treat them
differently?
Does the answer to my question depend on the version of PostgreSQL?
Thanks!
David J.