Tweak publication fetching in psql

Viewing a table with \d in psql also shows the publications at table is
in.  If a publication is concurrently dropped, this shows an error,
because the view pg_publication_tables internally uses
pg_get_publication_tables(), which uses a catalog snapshot.  This can be
particularly annoying if a for-all-tables publication is concurrently
dropped.

To avoid that, write the query in psql differently.  Expose the function
pg_relation_is_publishable() to SQL and write the query using that.
That still has a risk of being affected by concurrent catalog changes,
but in this case it would be a table drop that causes problems, and then
the psql \d command wouldn't be interesting anymore anyway.

Reported-by: Tom Lane <tgl@sss.pgh.pa.us>

1 files changed, 2 insertions, 0 deletions

diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index 73ce026d89..f22cc4f472 100644
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -5436,6 +5436,8 @@ DESCR("get progress for all replication origins");
 /* publications */
 DATA(insert OID = 6119 ( pg_get_publication_tables	PGNSP PGUID 12 1 1000 0 0 f f f f t t s s 1 0 26 "25" "{25,26}" "{i,o}" "{pubname,relid}" _null_ _null_ pg_get_publication_tables _null_ _null_ _null_ ));
 DESCR("get OIDs of tables in a publication");
+DATA(insert OID = 6121 ( pg_relation_is_publishable	PGNSP PGUID 12 1    0 0 0 f f f f t f s s 1 0 16 "2205" _null_ _null_ _null_ _null_ _null_ pg_relation_is_publishable _null_ _null_ _null_ ));
+DESCR("returns whether a relation can be part of a publication");
 
 /* rls */
 DATA(insert OID = 3298 (  row_security_active	   PGNSP PGUID 12 1 0 0 0 f f f f t f s s 1 0 16 "26" _null_ _null_ _null_ _null_ _null_	row_security_active _null_ _null_ _null_ ));