On Tue, Apr 27, 2021 at 12:23 PM Amul Sul <sula...@gmail.com> wrote: > > > > How about using an explain filter to replace the unstable text > > pg_temp_3 to pg_temp_N instead of changing it in the core? Following > > are the existing explain filters: explain_filter, > > explain_parallel_append, explain_analyze_without_memory, > > explain_resultcache, explain_parallel_sort_stats, explain_sq_limit. > > > > Well, yes eventually, that will be the kludge. I was wondering if that > table is accessible in a query via pg_temp schema then why should > bother about printing the pg_temp_N schema name which is an internal > purpose.
Although only the associated session can access objects from that schema, I think, the entries in pg_class have different namespace oids and are accessible from other sessions. So knowing the actual schema name is useful for debugging purposes. Using auto_explain, the explain output goes to server log, where access to two temporary tables with the same name from different sessions can be identified by the actual schema name easily. I am not sure whether we should change explain output only for the sake of stable tests. You could add a flag to EXPLAIN to mask pg_temp name but that's probably an overkill. Filtering is a better option for tests. -- Best Wishes, Ashutosh Bapat
