From e871a4a991762ec5312239aa1a1e0ff918d6ce90 Mon Sep 17 00:00:00 2001
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
Date: Mon, 5 Feb 2024 19:05:34 +0100
Subject: [PATCH v2 2/2] ATTACH PARTITION: Don't let a UNIQUE constraint match
 a PRIMARY KEY

---
 src/backend/commands/tablecmds.c    |  5 +++++
 src/backend/utils/cache/lsyscache.c | 25 +++++++++++++++++++++++++
 src/include/utils/lsyscache.h       |  2 ++
 3 files changed, 32 insertions(+)

diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 02724d5f04..cd4687fb7f 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -19269,6 +19269,11 @@ AttachPartitionEnsureIndexes(List **wqueue, Relation rel, Relation attachrel)
 					/* no dice */
 					if (!OidIsValid(cldConstrOid))
 						continue;
+
+					/* Ensure they're both the same type of constraint */
+					if (get_constraint_type(constraintOid) !=
+						get_constraint_type(cldConstrOid))
+						continue;
 				}
 
 				/* bingo. */
diff --git a/src/backend/utils/cache/lsyscache.c b/src/backend/utils/cache/lsyscache.c
index f730aa26c4..da737786ad 100644
--- a/src/backend/utils/cache/lsyscache.c
+++ b/src/backend/utils/cache/lsyscache.c
@@ -1132,6 +1132,31 @@ get_constraint_index(Oid conoid)
 		return InvalidOid;
 }
 
+/*
+ * get_constraint_type
+ *		Return the pg_constraint.contype value for the given constraint.
+ *
+ * No frills.
+ */
+char
+get_constraint_type(Oid conoid)
+{
+	HeapTuple	tp;
+
+	tp = SearchSysCache1(CONSTROID, ObjectIdGetDatum(conoid));
+	if (HeapTupleIsValid(tp))
+	{
+		Form_pg_constraint contup = (Form_pg_constraint) GETSTRUCT(tp);
+		char	result;
+
+		result = contup->contype;
+		ReleaseSysCache(tp);
+		return result;
+	}
+
+	return '\0';
+}
+
 /*				---------- LANGUAGE CACHE ----------					 */
 
 char *
diff --git a/src/include/utils/lsyscache.h b/src/include/utils/lsyscache.h
index e4a200b00e..fe694f5c4a 100644
--- a/src/include/utils/lsyscache.h
+++ b/src/include/utils/lsyscache.h
@@ -100,6 +100,8 @@ extern char *get_collation_name(Oid colloid);
 extern bool get_collation_isdeterministic(Oid colloid);
 extern char *get_constraint_name(Oid conoid);
 extern Oid	get_constraint_index(Oid conoid);
+extern char get_constraint_type(Oid conoid);
+
 extern char *get_language_name(Oid langoid, bool missing_ok);
 extern Oid	get_opclass_family(Oid opclass);
 extern Oid	get_opclass_input_type(Oid opclass);
-- 
2.39.2