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commit    ef3d7b15e4cd075b4e7f036ba151055d650b33c6
Author:   Heikki Linnakangas <heikki.linnakangas@iki.fi>
Date:     Wed May 27 15:35:55 2026 +0000

    Don't try to record dependency on a dropped column's datatype
    
    When creating a relation with a dropped column, we called
    recordDependencyOn() also on the datatype of the dropped column, which
    is always InvalidOid. In versions 15 and above, that was harmless
    because recordDependencyOn() considers InvalidOid as a pinned object,
    and skips over it. On version 14, isPinnedObject() does not consider
    InvalidOid as pinned, so we created a bogus pg_depend entry with
    refobjectid == 0.
    
    As far as I can tell, the only case when AddNewAttributeTuples() is
    called with dropped columns is when performing a table-rewriting ALTER
    TABLE command. That temporarily creates a new relation with the same
    columns, including dropped ones, then swaps the relations, and drops
    the newly created table again. So even on version 14, the bogus
    pg_depend entry was only on the transient relation that was dropped at
    the end of the ALTER TABLE command, which was harmless.
    
    Even though this is harmless, let's be tidy, similar to commit
    713bce9484. The reason I noticed this now and why I backported this,
    is because the next commit will add code to acquire locks on the
    referenced objects, and we don't want to acquire a lock on InvalidOid.
    
    Discussion: https://postgr.es/m/ZiYjn0eVc7pxVY45@ip-10-97-1-34.eu-west-3.compute.internal
    Backpatch-through: 14


 src/backend/catalog/heap.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/backend/catalog/heap.c b/src/backend/catalog/heap.c
index 3dc1e38ada0..987c863bfb5 100644
--- a/src/backend/catalog/heap.c
+++ b/src/backend/catalog/heap.c
@@ -844,6 +844,9 @@ AddNewAttributeTuples(Oid new_rel_oid,
 	/* add dependencies on their datatypes and collations */
 	for (int i = 0; i < natts; i++)
 	{
+		if (tupdesc->attrs[i].attisdropped)
+			continue;
+
 		/* Add dependency info */
 		ObjectAddressSubSet(myself, RelationRelationId, new_rel_oid, i + 1);
 		ObjectAddressSet(referenced, TypeRelationId,


[parent: 2dfe75f9844f]