From c8afb42bc44ab8cc6349bd53614bb6da72da7afa Mon Sep 17 00:00:00 2001
From: Justin Pryzby <pryzbyj@telsasoft.com>
Date: Thu, 5 Nov 2020 18:58:03 -0600
Subject: [PATCH v7 4/7] Invalidate parent indexes

---
 src/backend/commands/cluster.c        | 21 +++++++++++++++++++++
 src/test/regress/expected/cluster.out | 26 ++++++++++++++++++++++++++
 src/test/regress/sql/cluster.sql      |  8 ++++++++
 3 files changed, 55 insertions(+)

diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c
index 78c2c2ba72..05c84e5582 100644
--- a/src/backend/commands/cluster.c
+++ b/src/backend/commands/cluster.c
@@ -594,6 +594,27 @@ mark_index_clustered(Relation rel, Oid indexOid, bool is_internal)
 	}
 	list_free(inh);
 
+	/*
+	 * Set parent of all indexes as unclustered when a rel is unclustered; and,
+	 * when an index is clustered, set parents of all /other/ indexes as
+	 * unclustered.
+	 */
+	indexes = RelationGetIndexList(rel);
+	foreach (lc, indexes)
+	{
+		Oid	thisIndexOid = lfirst_oid(lc);
+
+		if (thisIndexOid == indexOid)
+			continue;
+
+		while (get_rel_relispartition(thisIndexOid))
+		{
+			thisIndexOid = get_partition_parent(thisIndexOid);
+			set_indisclustered(thisIndexOid, false, pg_index);
+		}
+	}
+	list_free(indexes);
+
 	table_close(pg_index, RowExclusiveLock);
 }
 
diff --git a/src/test/regress/expected/cluster.out b/src/test/regress/expected/cluster.out
index 1d436dfaae..6cba3cc4f9 100644
--- a/src/test/regress/expected/cluster.out
+++ b/src/test/regress/expected/cluster.out
@@ -541,6 +541,32 @@ Indexes:
     "clstrpart1_idx_2" btree (a) CLUSTER
 Number of partitions: 2 (Use \d+ to list them.)
 
+-- Check that the parent index is marked not clustered after clustering a partition on a different index:
+ALTER TABLE clstrpart CLUSTER ON clstrpart_idx;
+CLUSTER clstrpart1 USING clstrpart1_idx_2;
+\d clstrpart
+       Partitioned table "public.clstrpart"
+ Column |  Type   | Collation | Nullable | Default 
+--------+---------+-----------+----------+---------
+ a      | integer |           |          | 
+Partition key: RANGE (a)
+Indexes:
+    "clstrpart_idx" btree (a)
+Number of partitions: 3 (Use \d+ to list them.)
+
+-- Check that the parent index is marked not clustered after setting a partition not clustered:
+ALTER TABLE clstrpart CLUSTER ON clstrpart_idx;
+ALTER TABLE clstrpart1 SET WITHOUT CLUSTER;
+\d clstrpart
+       Partitioned table "public.clstrpart"
+ Column |  Type   | Collation | Nullable | Default 
+--------+---------+-----------+----------+---------
+ a      | integer |           |          | 
+Partition key: RANGE (a)
+Indexes:
+    "clstrpart_idx" btree (a)
+Number of partitions: 3 (Use \d+ to list them.)
+
 -- Test CLUSTER with external tuplesorting
 create table clstr_4 as select * from tenk1;
 create index cluster_sort on clstr_4 (hundred, thousand, tenthous);
diff --git a/src/test/regress/sql/cluster.sql b/src/test/regress/sql/cluster.sql
index 0ded2be1ca..a1d132f288 100644
--- a/src/test/regress/sql/cluster.sql
+++ b/src/test/regress/sql/cluster.sql
@@ -231,6 +231,14 @@ CREATE INDEX clstrpart1_idx_2 ON clstrpart1(a);
 ALTER TABLE clstrpart CLUSTER ON clstrpart_idx;
 ALTER TABLE clstrpart1 CLUSTER ON clstrpart1_idx_2;
 \d clstrpart1
+-- Check that the parent index is marked not clustered after clustering a partition on a different index:
+ALTER TABLE clstrpart CLUSTER ON clstrpart_idx;
+CLUSTER clstrpart1 USING clstrpart1_idx_2;
+\d clstrpart
+-- Check that the parent index is marked not clustered after setting a partition not clustered:
+ALTER TABLE clstrpart CLUSTER ON clstrpart_idx;
+ALTER TABLE clstrpart1 SET WITHOUT CLUSTER;
+\d clstrpart
 
 -- Test CLUSTER with external tuplesorting
 
-- 
2.17.0

