pg_filenode_relation(0,0) elog
Per sqlsmith.
postgres=# SELECT pg_filenode_relation(0,0);
ERROR: unexpected duplicate for tablespace 0, relfilenode 0
postgres=# \errverbose
ERROR: XX000: unexpected duplicate for tablespace 0, relfilenode 0
LOCATION: RelidByRelfilenode, relfilenodemap.c:220
The usual expectation is that sql callable functions should return null rather
than hitting elog(). This also means that sqlsmith has one fewer
false-positive error.
I think it should return NULL if passed invalid relfilenode, rather than
searching pg_class and then writing a pretty scary message about duplicates.
diff --git a/src/backend/utils/cache/relfilenodemap.c b/src/backend/utils/cache/relfilenodemap.c
index 56d7c73d33..5a5cf853bd 100644
--- a/src/backend/utils/cache/relfilenodemap.c
+++ b/src/backend/utils/cache/relfilenodemap.c
@@ -146,6 +146,9 @@ RelidByRelfilenode(Oid reltablespace, Oid relfilenode)
ScanKeyData skey[2];
Oid relid;+ if (!OidIsValid(relfilenode))
+ return InvalidOid;
+
if (RelfilenodeMapHash == NULL)
InitializeRelfilenodeMap();
Justin Pryzby <pryzby@telsasoft.com> writes:
Per sqlsmith.
postgres=# SELECT pg_filenode_relation(0,0);
ERROR: unexpected duplicate for tablespace 0, relfilenode 0
Ugh.
The usual expectation is that sql callable functions should return null rather
than hitting elog().
Agreed, but you should put the short-circuit into the SQL-callable
function, ie pg_filenode_relation. Lower-level callers ought not be
passing junk data.
Likely it should check the reltablespace, too.
regards, tom lane
On Fri, Jun 11, 2021 at 11:51:35PM -0400, Tom Lane wrote:
Justin Pryzby <pryzby@telsasoft.com> writes:
Per sqlsmith.
postgres=# SELECT pg_filenode_relation(0,0);
ERROR: unexpected duplicate for tablespace 0, relfilenode 0Ugh.
The usual expectation is that sql callable functions should return null rather
than hitting elog().Agreed, but you should put the short-circuit into the SQL-callable
function, ie pg_filenode_relation. Lower-level callers ought not be
passing junk data.
Right. I spent inadequate time reading output of git grep.
Likely it should check the reltablespace, too.
I don't think so. The docs say:
https://www.postgresql.org/docs/current/functions-admin.html#FUNCTIONS-ADMIN-DBLOCATION
|For a relation in the database's default tablespace, the tablespace can be specified as zero.
Also, that would breaks expected/alter_table.out for the same reason.
diff --git a/src/backend/utils/adt/dbsize.c b/src/backend/utils/adt/dbsize.c
index 3c70bb5943..144aca1099 100644
--- a/src/backend/utils/adt/dbsize.c
+++ b/src/backend/utils/adt/dbsize.c
@@ -905,6 +905,9 @@ pg_filenode_relation(PG_FUNCTION_ARGS)
Oid relfilenode = PG_GETARG_OID(1);
Oid heaprel = InvalidOid;+ if (!OidIsValid(relfilenode))
+ PG_RETURN_NULL();
+
heaprel = RelidByRelfilenode(reltablespace, relfilenode);if (!OidIsValid(heaprel))
Justin Pryzby <pryzby@telsasoft.com> writes:
On Fri, Jun 11, 2021 at 11:51:35PM -0400, Tom Lane wrote:
Likely it should check the reltablespace, too.
I don't think so. The docs say:
https://www.postgresql.org/docs/current/functions-admin.html#FUNCTIONS-ADMIN-DBLOCATION
|For a relation in the database's default tablespace, the tablespace can be specified as zero.
Right, my mistake. Pushed.
regards, tom lane