Re: Should we add GUCs to allow partition pruning to be disabled?

David Rowley wrote:
> On 10 May 2018 at 14:01, Alvaro Herrera <alvherre(at)2ndquadrant(dot)com> wrote:
> > I'm thinking something a bit more radical. First, since partition
> > pruning is the future and constraint exclusion is soon to be a thing of
> > the past, we should describe pruning first, and then describe exclusion
> > in terms of pruning.
>
> But... that's not true. The chapter describes inheritance partitioned
> tables too, and we're not getting rid of constraint exclusion because
> it's needed for those.

Oh, I'm sure it is, but nobody is going to set up new inheritance
partitioned tables anymore, except people who pg_upgrade from older
releases. (And while I haven't tried, I'm sure it's possible to migrate
from old-style to new-style partitioned tables without incurring full
table rewrites, with little downside and lots to gain.)

Now, maybe you argue that we could have a structure like this instead:

5.10.1. Overview
5.10.2. Declarative Partitioning
5.10.3. Partition Pruning
5.10.4. Implementation Using Inheritance
5.10.5. Constraint Exclusion

I wouldn't oppose that.

> However, that might not mean your patch has to be changed. I'd better
> have a look...

Thanks :-)

--
Álvaro Herrera https://www.2ndQuadrant.com/
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