Re: CLUSTER on partitioned index

On Sun, Nov 15, 2020 at 07:53:35PM -0600, Justin Pryzby wrote:
> On Wed, Nov 04, 2020 at 08:23:56PM -0600, Justin Pryzby wrote:
> > On Tue, Oct 27, 2020 at 07:33:12PM -0500, Justin Pryzby wrote:
> > > I'm attaching a counter-proposal to your catalog change, which preserves
> > > indisclustered on children of clustered, partitioned indexes, and invalidates
> > > indisclustered when attaching unclustered indexes.
> >
> > ..and now propagates CLUSTER ON to child indexes.
> >
> > I left this as separate patches to show what I mean and what's new while we
> > discuss it.
>
> This fixes some omissions in the previous patch and error in its test cases.
>
> CLUSTER ON recurses to children, since I think a clustered parent index means
> that all its child indexes are clustered. "SET WITHOUT CLUSTER" doesn't have
> to recurse to children, but I did it like that for consistency and it avoids
> the need to special case InvalidOid.

The previous patch failed pg_upgrade when restoring a clustered, parent index,
since it's marked INVALID until indexes have been built on all child tables, so
CLUSTER ON was rejected on invalid index.

So I think CLUSTER ON needs to be a separate pg_dump object, to allow attaching
the child index (thereby making the parent "valid") to happen before SET
CLUSTER on the parent index.

--
Justin