On Thu, Sep 4, 2014 at 11:07 AM, Pavel Stehule <pavel.stehule@gmail.com> wrote:
> it is different semantic - returns composite or set of composites --- it is
> not row or rows
The point was, RETURNS returns 1 while RETURNS SETOF returns 0 .. n.
> Actually BL is usually processed oriented, so PL functions coverages changes
> in data, and for queries you use SELECT
OK, so you SELECT directly from tables?
And in the PLs you change a lot of rows in the same txn?
> Returning SET from function is less often - and usually it is not in
> preferred patterns because you can very simple block a optimizer.
Not if you do all access, also SELECT via PLs, then you might want to returns
lists of things based on some input.
But that's a different topic. What I wanted to examplify is the fact
we *already*
have a lot of syntax which handles the 1 row case in a special way.