Re: Implement targetlist SRFs using ROWS FROM() (was Changed SRF in targetlist handling)

Andres Freund <andres(at)anarazel(dot)de> writes:
> On 2016-09-15 16:48:59 -0400, Tom Lane wrote:
>> The patch that I posted would run both the generate_series(1, 2) and
>> generate_series(2,4) calls in the same SRF node, forcing them to run in
>> lockstep, after which their results would be fed to the SRF node doing
>> the top-level SRFs. We could probably change it to run them in separate
>> nodes, but I don't see any principled way to decide which one goes first
>> (and in some variants of this example, it would matter).

> I think that's fine. I personally still think we're *much* better off
> getting rid of the non-lockstep variants. You're still on the fence
> about retaining the LCM behaviour (for the same nesting level at least)?

I'm happy to get rid of the LCM behavior, I just want to have some wiggle
room to be able to get it back if somebody really needs it.

regards, tom lane