Re: FailedAssertion("pd_idx == pinfo->nparts", File: "execPartition.c", Line: 1689)

On Wed, Aug 5, 2020 at 4:19 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
> After thinking about it for a little bit, I'm envisioning a test module
> that can be loaded into a session, and then it gets into the planner_hook,
> and what it does is after each planner execution, take and release an
> advisory lock with some selectable ID.  Then we can construct
> isolationtester specs that do something like
>
>         session 1                               session 2
>
>         LOAD test-module;
>         SET custom_guc_for_lock_id = n;
>         prepare test tables;
>
>                                                 SELECT pg_advisory_lock(n);
>
>         SELECT victim-query-here;
>         ... after planning, query blocks on lock
>
>                                                 perform DDL changes;
>                                                 SELECT pg_advisory_unlock(n);
>
>         ... query executes with now-stale plan

Very sneaky!

-- 
Robert Haas
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