Re: CREATE INDEX CONCURRENTLY on partitioned index

On Sun, 2022-12-04 at 13:09 -0600, Justin Pryzby wrote:
>
> This beavior is fixed.  I re-factored and re-implented to use
> DefineIndex() for building indexes concurrently rather than
> reindexing.
> That makes the patch smaller, actually, and has the added benefit of
> splitting off the "Concurrently" part of DefineIndex() into a
> separate
> function.

Nice, I think it turned out pretty concise. I played around with the
patch quite a bit, didn't find any major problems, the only minor thing
that I can note is that we should skip the top parent index itself in
the loop not to increment the pg_stat counter, something like this:

diff --git a/src/backend/commands/indexcmds.c
b/src/backend/commands/indexcmds.c
index cfab45b999..9049540b5b 100644
--- a/src/backend/commands/indexcmds.c
+++ b/src/backend/commands/indexcmds.c
@@ -1515,6 +1515,9 @@ DefineIndex(Oid relationId,
Oid indrelid =
lfirst_oid(lc);
Oid tabrelid =
IndexGetRelation(indrelid, false);

+ if (indrelid == indexRelationId)
+ continue;
+
if
(RELKIND_HAS_STORAGE(get_rel_relkind(indrelid)) &&
!get_index_isvalid(indrelid))
{
>
> BTW, it causes the patch to fail to apply in cfbot when you send an
> additional (002) supplementary patch without including the original
> (001) patch.  You can name it *.txt to avoid the issue.
>
> https://wiki.postgresql.org/wiki/Cfbot#Which_attachments_are_considered_to_be_patches.3F
>
> Thanks for looking.
>
My bad, didn't know about this, thanks for the link.

On a side note, I noticed that reindex behaviour is strange on
partitioned tables, it doesn't mark partitioned tables as valid after
reindexing children, as I could understand from the code and mailing
lists, this is the intended behaviour, but I can't quite understand the
rationale for it, do you know why it is done this way?