Re: SPLIT/MERGE use of is_internal=true

On Wed, Jul 08, 2026 at 02:49:45AM +0300, Alexander Korotkov wrote:
> On Tue, Jul 7, 2026 at 9:57 PM Noah Misch <noah(at)leadboat(dot)com> wrote:
> > This and other places in the SPLIT/MERGE patches pass is_internal=true, which
> > ultimately flows to hooks with the following meaning:
> >
> > /*
> > * If this flag is set, the user hasn't requested that the object be
> > * altered, but we're doing it anyway for some internal reason.
> > * Permissions-checking hooks may want to skip checks if, say, we're alter
> > * the constraints of a temporary heap during CLUSTER.
> > */
> > bool is_internal;
> >
> > SPLIT/MERGE constitute user requests to create and/or drop tables, so they're
> > not like a CLUSTER temporary heap. They should pass is_internal=false, like
> > when the user runs CREATE/DROP directly.
>
> Thank you for catching this. For sure, we shouldn't pass
> is_internal=true here. Attached patch fixes this. I'm going to push
> it if no objections.

> Subject: [PATCH v1] Don't create SPLIT/MERGE partitions as internal relations
>
> createPartitionTable(), which builds the new partitions for ALTER TABLE
> ... SPLIT PARTITION and ALTER TABLE ... MERGE PARTITIONS, passed
> is_internal=true to heap_create_with_catalog(). These relations are
> created at the explicit request of the user, just like a plain CREATE
> TABLE, so pass is_internal=false instead. The is_internal flag is meant
> for objects created as an internal implementation detail (for example, a
> transient heap built during CLUSTER), and it is observed by
> object-access hooks.
>
> Reported-by: Noah Misch <noah(at)leadboat(dot)com>
> Discussion: https://postgr.es/m/20260707185751.f9.noahmisch@microsoft.com

Log should have a "Backpatch-through: 19" line.

> ---
> src/backend/commands/tablecmds.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
> index 95abaf4890c..0b6a84b32b7 100644
> --- a/src/backend/commands/tablecmds.c
> +++ b/src/backend/commands/tablecmds.c
> @@ -23137,7 +23137,7 @@ createPartitionTable(List **wqueue, RangeVar *newPartName,
> (Datum) 0,
> true,
> allowSystemTableMods,
> - true,
> + false, /* is_internal */
> InvalidOid,
> NULL);

The edit looks fine for this code site. As I mentioned above, other
SPLIT/MERGE code sites need the same change.