Re: Making Vars outer-join aware

Justin Pryzby <pryzby@telsasoft.com>

From: Justin Pryzby <pryzby@telsasoft.com>

To: Richard Guo <guofenglinux@gmail.com>

Cc: Tom Lane <tgl@sss.pgh.pa.us>, pgsql-hackers@lists.postgresql.org, "Finnerty, Jim" <jfinnert@amazon.com>

Date: 2023-02-13T18:48:07Z

Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

Re-allow INDEX_VAR as rt_index in ChangeVarNodes().
- fbf80421ead5 16.0 landed
Fix thinkos in have_unsafe_outer_join_ref; reduce to Assert check.
- f50f029c497d 16.0 landed
Invent "join domains" to replace the below_outer_join hack.
- 3bef56e11650 16.0 landed
Do assorted mop-up in the planner.
- b448f1c8d83f 16.0 landed
Make Vars be outer-join-aware.
- 2489d76c4906 16.0 landed
Invent "multibitmapsets", and use them to speed up antijoin detection.
- e9e26b5e7166 16.0 landed
Add basic regression tests for semi/antijoin recognition.
- 0043aa6b8597 16.0 landed
Improve performance of adjust_appendrel_attrs_multilevel.
- 2f17b57017e5 16.0 landed
Refactor addition of PlaceHolderVars to joinrel targetlists.
- afa0ec30bfd1 16.0 landed
Use an explicit state flag to control PlaceHolderInfo creation.
- b3ff6c742f6c 16.0 landed
Make PlaceHolderInfo lookup O(1).
- 6569ca43973b 16.0 landed

On Mon, Feb 13, 2023 at 03:33:15PM +0800, Richard Guo wrote:
> On Mon, Feb 13, 2023 at 7:58 AM Justin Pryzby <pryzby@telsasoft.com> wrote:
> > The patch broke this query:
> >
> > select from pg_inherits inner join information_schema.element_types
> > right join (select from pg_constraint as sample_2) on true
> > on false, lateral (select scope_catalog, inhdetachpending from
> > pg_publication_namespace limit 3);
> > ERROR:  could not devise a query plan for the given query

> BTW, here is a simplified query that can trigger this issue on HEAD.
> 
> select * from t1 inner join t2 left join (select null as c from t3 left
> join t4 on true) as sub on true on true, lateral (select c, t1.a from t5
> offset 0 ) ss;

It probably doesn't need to be said that the original query was reduced
from sqlsmith...  But I mention that now to make it searchable.

Thanks,
-- 
Justin