[#23118] YSQL: Add support for ADD PRIMARY KEY ... USING INDEX

Summary: This diff adds support for adding a primary key using a unique index by performing table rewrite. Code changes: - ATExecAddIndexConstraint in tablecmds.c: - If we are adding a primary key constraint on a YB relation, mark the table to be rewritten by alter table phase 3. - Skip copying split options (number of tablets) when we are adding a range based primary key. - Since primary keys are implicit to the DocDB table, drop the DocDB table associated with the secondary unique index. - pg_yb_utils.c: - Add function `YbGetIndexKeySortOrdering` to retrieve the sort ordering of the first key element of an index. - YbATIsRangePk: minor change to make the function take the sort ordering instead as a parameter instead of the index statement. Note: This operation is not supported when the unique index has key columns in descending order -- this limitation exists in Postgres, as Postgres does not allow adding primary keys with `DESC` ordering. Although we can support this in YB, it is omitted for now as the motivation for this feature is to facilitate migrations. Jira: DB-12051 Test Plan: new tests in `yb_alter_table_rewrite`, `yb_pg_create_index`, `yb_pg_index_including` ./yb_build.sh --java-test 'org.yb.pgsql.TestPgRegressTable' ./yb_build.sh --java-test 'org.yb.pgsql.TestPgRegressPgMisc' ./yb_build.sh --java-test 'org.yb.pgsql.TestPgRegressPgMiscIndependent' Reviewers: myang Reviewed By: myang Subscribers: smishra, yql Differential Revision: https://phorge.dev.yugabyte.com/D37741
yugabyte · Sep 13, 2024 · 2ac2e98 · 2ac2e98
1 parent 24a5af0
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diff --git a/src/postgres/src/backend/commands/tablecmds.c b/src/postgres/src/backend/commands/tablecmds.c
@@ -444,7 +444,7 @@ static ObjectAddress ATExecAddConstraint(List **wqueue,
 					Constraint *newConstraint, bool recurse, bool is_readd,
 					LOCKMODE lockmode);
 static ObjectAddress ATExecAddIndexConstraint(AlteredTableInfo *tab, Relation rel,
-						 IndexStmt *stmt, LOCKMODE lockmode);
+						 IndexStmt *stmt, LOCKMODE lockmode, List **yb_wqueue);
 static ObjectAddress ATAddCheckConstraint(List **wqueue,
 					 AlteredTableInfo *tab, Relation rel,
 					 Constraint *constr,
@@ -551,8 +551,8 @@ static Relation YbATCloneRelationSetColumnType(Relation old_rel,
 											   Oid altered_collation_id,
 											   TypeName *altered_type_name,
 											   List *new_column_values);
-static bool YbATIsRangePk(IndexStmt *stmt,
-						  bool is_colocated, bool is_tablegroup);
+static bool YbATIsRangePk(SortByDir ordering, bool is_colocated,
+						  bool is_tablegroup);
 static void YbATSetPKRewriteChildPartitions(List **yb_wqueue,
 											AlteredTableInfo *tab,
 											bool skip_copy_split_options);
@@ -4631,7 +4631,7 @@ ATExecCmd(List **wqueue, AlteredTableInfo *tab, Relation *mutable_rel,
 			break;
 		case AT_AddIndexConstraint: /* ADD CONSTRAINT USING INDEX */
 			address = ATExecAddIndexConstraint(tab, rel, (IndexStmt *) cmd->def,
-											   lockmode);
+											   lockmode, wqueue);
 			break;
 		case AT_AlterConstraint:	/* ALTER CONSTRAINT */
 			address = ATExecAlterConstraint(rel, cmd, false, false, lockmode);
@@ -7639,7 +7639,8 @@ ATExecAddIndex(List **yb_wqueue, AlteredTableInfo *tab, Relation *mutable_rel,
 		{
 			YbGetTableProperties(*mutable_rel);
 			/* Don't copy split options if we are creating a range key. */
-			bool skip_copy_split_options = YbATIsRangePk(stmt,
+			bool skip_copy_split_options = YbATIsRangePk(
+				linitial_node(IndexElem, stmt->indexParams)->ordering,
 				(*mutable_rel)->yb_table_properties->is_colocated, OidIsValid(
 					(*mutable_rel)->yb_table_properties->tablegroup_oid));
 			if (!skip_build)
@@ -7683,7 +7684,8 @@ ATExecAddIndex(List **yb_wqueue, AlteredTableInfo *tab, Relation *mutable_rel,
  */
 static ObjectAddress
 ATExecAddIndexConstraint(AlteredTableInfo *tab, Relation rel,
-						 IndexStmt *stmt, LOCKMODE lockmode)
+						 IndexStmt *stmt, LOCKMODE lockmode,
+						 List **yb_wqueue)
 {
 	Oid			index_oid = stmt->indexOid;
 	Relation	indexRel;
@@ -7707,11 +7709,6 @@ ATExecAddIndexConstraint(AlteredTableInfo *tab, Relation rel,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("ALTER TABLE / ADD CONSTRAINT USING INDEX is not supported on partitioned tables")));
 
-	if (IsYugaByteEnabled() && stmt->primary)
-		ereport(ERROR,
-				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-				 errmsg("ALTER TABLE / ADD CONSTRAINT PRIMARY KEY USING INDEX is not supported")));
-
 	indexRel = index_open(index_oid, AccessShareLock);
 
 	indexName = pstrdup(RelationGetRelationName(indexRel));
@@ -7722,6 +7719,29 @@ ATExecAddIndexConstraint(AlteredTableInfo *tab, Relation rel,
 	if (!indexInfo->ii_Unique)
 		elog(ERROR, "index \"%s\" is not unique", indexName);
 
+	/*
+	 * YB: Adding a primary key requires table rewrite.
+	 * We do not need to rewrite any children as this operation is not supported
+	 * on partitioned tables (checked above).
+	 */
+	if (IsYBRelation(rel) && stmt->primary)
+	{
+		YbGetTableProperties(rel);
+		/* Don't copy split options if we are creating a range key. */
+		bool skip_copy_split_options = YbATIsRangePk(
+			YbGetIndexKeySortOrdering(indexRel),
+			rel->yb_table_properties->is_colocated, OidIsValid(
+				rel->yb_table_properties->tablegroup_oid));
+		tab->rewrite |= YB_AT_REWRITE_ALTER_PRIMARY_KEY;
+		tab->yb_skip_copy_split_options = tab->yb_skip_copy_split_options
+			|| skip_copy_split_options;
+		/*
+		 * Since this index is going to be upgraded to a pkey, we can drop the
+		 * DocDB table associated with the secondary index.
+		 */
+		YBCDropIndex(indexRel);
+	}
+
 	/*
 	 * Determine name to assign to constraint.  We require a constraint to
 	 * have the same name as the underlying index; therefore, use the index's
@@ -16249,7 +16269,8 @@ AttachPartitionEnsureIndexes(Relation rel, Relation attachrel, List **yb_wqueue)
 				tab->rewrite = YB_AT_REWRITE_ALTER_PRIMARY_KEY;
 				YbGetTableProperties(attachrel);
 				/* Don't copy split options if we are creating a range key. */
-				bool skip_copy_split_options = YbATIsRangePk(stmt,
+				bool skip_copy_split_options = YbATIsRangePk(
+					linitial_node(IndexElem, stmt->indexParams)->ordering,
 					attachrel->yb_table_properties->is_colocated,
 					OidIsValid(
 						attachrel->yb_table_properties->tablegroup_oid));
@@ -17596,11 +17617,11 @@ YbATGetRenameStmt(const char *namespace_name, const char *current_name,
 }
 
 static bool
-YbATIsRangePk(IndexStmt *stmt, bool is_colocated, bool is_tablegroup)
+YbATIsRangePk(SortByDir ordering, bool is_colocated, bool is_tablegroup)
 {
 	SortByDir yb_ordering =
-		YbSortOrdering(linitial_node(IndexElem, stmt->indexParams)->ordering,
-					   is_colocated, is_tablegroup, true /* is_first_key */);
+		YbSortOrdering(ordering, is_colocated, is_tablegroup,
+					   true /* is_first_key */);
 
 	if (yb_ordering == SORTBY_ASC || yb_ordering == SORTBY_DESC)
 		return true;
@@ -18924,7 +18945,8 @@ YbATCloneRelationSetPrimaryKey(Relation old_rel, IndexStmt *stmt,
 
 	if (stmt)
 		is_range_pk = YbATIsRangePk(
-			stmt, old_rel->yb_table_properties->is_colocated,
+			linitial_node(IndexElem, stmt->indexParams)->ordering,
+			old_rel->yb_table_properties->is_colocated,
 			OidIsValid(old_rel->yb_table_properties->tablegroup_oid));
 
 	/*

diff --git a/src/postgres/src/backend/utils/misc/pg_yb_utils.c b/src/postgres/src/backend/utils/misc/pg_yb_utils.c
@@ -5012,3 +5012,19 @@ bool YbIsAttrPrimaryKeyColumn(Relation rel, AttrNumber attnum)
 	return bms_is_member(attnum -
 		YBGetFirstLowInvalidAttributeNumber(rel), pkey);
 }
+
+/* Retrieve the sort ordering of the first key element of an index. */
+SortByDir YbGetIndexKeySortOrdering(Relation indexRel)
+{
+	if (IndexRelationGetNumberOfKeyAttributes(indexRel) == 0)
+		return SORTBY_DEFAULT;
+	/*
+	 * If there are key columns, check the indoption of the first
+	 * key attribute.
+	 */
+	if (indexRel->rd_indoption[0] & INDOPTION_HASH)
+		return SORTBY_HASH;
+	if (indexRel->rd_indoption[0] & INDOPTION_DESC)
+		return SORTBY_DESC;
+	return SORTBY_ASC;
+}
diff --git a/src/postgres/src/include/pg_yb_utils.h b/src/postgres/src/include/pg_yb_utils.h
@@ -1177,4 +1177,6 @@ extern bool YbIsYsqlConnMgrWarmupModeEnabled();
 
 bool YbIsAttrPrimaryKeyColumn(Relation rel, AttrNumber attnum);
 
+SortByDir YbGetIndexKeySortOrdering(Relation indexRel);
+
 #endif /* PG_YB_UTILS_H */
diff --git a/src/postgres/src/test/regress/expected/yb_alter_table_rewrite.out b/src/postgres/src/test/regress/expected/yb_alter_table_rewrite.out
@@ -293,6 +293,21 @@ SELECT num_tablets, num_hash_key_columns, is_colocated FROM
            1 |                    0 | t
 (1 row)
 
+CREATE UNIQUE INDEX base_idx_unique ON base(col);
+ALTER TABLE base ADD PRIMARY KEY USING INDEX base_idx_unique;
+INSERT INTO base VALUES (1, 1); -- should fail.
+ERROR:  duplicate key value violates unique constraint "base_idx_unique"
+INSERT INTO base VALUES (4, 4), (5, 5);
+SELECT col, col2 FROM base;
+ col | col2
+-----+------
+   1 |    3
+   2 |    2
+   3 |    1
+   4 |    4
+   5 |    5
+(5 rows)
+
 CREATE TABLE base2 (col int, col2 int) WITH (COLOCATION=false);
 CREATE INDEX base2_idx ON base2(col2);
 INSERT INTO base2 VALUES (1, 3), (2, 2), (3, 1);
@@ -592,10 +607,66 @@ CREATE TABLE nopk_udt (id typeid, v int);
 ALTER TABLE nopk_udt ADD PRIMARY KEY (id); -- should fail.
 ERROR:  PRIMARY KEY containing column of type 'user_defined_type' not yet supported
 -- test pk USING INDEX.
-CREATE TABLE nopk_usingindex (id int);
-CREATE UNIQUE INDEX nopk_idx ON nopk_usingindex (id ASC);
+CREATE TABLE nopk_usingindex (id int) SPLIT INTO 5 TABLETS;
+INSERT INTO nopk_usingindex VALUES (1), (2), (3);
+CREATE INDEX nopk_idx ON nopk_usingindex(id);
+CREATE UNIQUE INDEX nopk_idx2 ON nopk_usingindex (id HASH);
+CREATE UNIQUE INDEX nopk_idx3 ON nopk_usingindex (id ASC);
+CREATE UNIQUE INDEX nopk_idx4 ON nopk_usingindex (id DESC);
 ALTER TABLE nopk_usingindex ADD PRIMARY KEY USING INDEX nopk_idx; -- should fail.
-ERROR:  ALTER TABLE / ADD CONSTRAINT PRIMARY KEY USING INDEX is not supported
+ERROR:  "nopk_idx" is not a unique index
+LINE 1: ALTER TABLE nopk_usingindex ADD PRIMARY KEY USING INDEX nopk...
+                                        ^
+DETAIL:  Cannot create a primary key or unique constraint using such an index.
+INSERT INTO nopk_usingindex VALUES (null);
+ALTER TABLE nopk_usingindex ADD PRIMARY KEY USING INDEX nopk_idx2; -- should fail.
+ERROR:  column "id" contains null values
+DELETE FROM nopk_usingindex WHERE id IS NULL;
+ALTER TABLE nopk_usingindex ADD PRIMARY KEY USING INDEX nopk_idx2;
+SELECT num_tablets, num_hash_key_columns FROM yb_table_properties('nopk_usingindex'::regclass);
+ num_tablets | num_hash_key_columns
+-------------+----------------------
+           5 |                    1
+(1 row)
+
+INSERT INTO nopk_usingindex VALUES (4);
+INSERT INTO nopk_usingindex VALUES (1); -- should fail.
+ERROR:  duplicate key value violates unique constraint "nopk_idx2"
+INSERT INTO nopk_usingindex VALUES (null); -- should fail.
+ERROR:  null value in column "id" violates not-null constraint
+DETAIL:  Failing row contains (null).
+SELECT * FROM nopk_usingindex ORDER BY id;
+ id
+----
+  1
+  2
+  3
+  4
+(4 rows)
+
+DROP INDEX nopk_idx2; -- should fail.
+ERROR:  cannot drop index nopk_idx2 because constraint nopk_idx2 on table nopk_usingindex requires it
+HINT:  You can drop constraint nopk_idx2 on table nopk_usingindex instead.
+ALTER TABLE nopk_usingindex DROP CONSTRAINT nopk_idx2;
+ALTER TABLE nopk_usingindex ADD PRIMARY KEY USING INDEX nopk_idx3;
+SELECT * FROM nopk_usingindex;
+ id
+----
+  1
+  2
+  3
+  4
+(4 rows)
+
+DROP INDEX nopk_idx3; -- should fail.
+ERROR:  cannot drop index nopk_idx3 because constraint nopk_idx3 on table nopk_usingindex requires it
+HINT:  You can drop constraint nopk_idx3 on table nopk_usingindex instead.
+ALTER TABLE nopk_usingindex DROP CONSTRAINT nopk_idx3;
+ALTER TABLE nopk_usingindex ADD PRIMARY KEY USING INDEX nopk_idx4; -- should fail (not supported in PG).
+ERROR:  index "nopk_idx4" does not have default sorting behavior
+LINE 1: ALTER TABLE nopk_usingindex ADD PRIMARY KEY USING INDEX nopk...
+                                        ^
+DETAIL:  Cannot create a primary key or unique constraint using such an index.
 -- test adding/dropping pks on partitioned tables.
 CREATE TABLE nopk_whole (id int) PARTITION BY LIST (id);
 CREATE TABLE nopk_part1 PARTITION OF nopk_whole FOR VALUES IN (1, 2, 3);

diff --git a/src/postgres/src/test/regress/expected/yb_pg_create_index.out b/src/postgres/src/test/regress/expected/yb_pg_create_index.out
@@ -152,6 +152,71 @@ LINE 1: REINDEX TABLE concur_heap;
                 ^
 HINT:  Please report the issue on https://github.com/YugaByte/yugabyte-db/issues
 --
+-- Test ADD CONSTRAINT USING INDEX
+--
+CREATE TABLE cwi_test( a int , b varchar(10), c char);
+-- add some data so that all tests have something to work with.
+INSERT INTO cwi_test VALUES(1, 2), (3, 4), (5, 6);
+CREATE UNIQUE INDEX cwi_uniq_idx ON cwi_test(a , b);
+ALTER TABLE cwi_test ADD primary key USING INDEX cwi_uniq_idx;
+NOTICE:  table rewrite may lead to inconsistencies
+DETAIL:  Concurrent DMLs may not be reflected in the new table.
+HINT:  See https://github.com/yugabyte/yugabyte-db/issues/19860. Set 'ysql_suppress_unsafe_alter_notice' yb-tserver gflag to true to suppress this notice.
+\d cwi_test
+                     Table "public.cwi_test"
+ Column |         Type          | Collation | Nullable | Default
+--------+-----------------------+-----------+----------+---------
+ a      | integer               |           | not null |
+ b      | character varying(10) |           | not null |
+ c      | character(1)          |           |          |
+Indexes:
+    "cwi_uniq_idx" PRIMARY KEY, lsm (a HASH, b ASC)
+
+\d cwi_uniq_idx
+            Index "public.cwi_uniq_idx"
+ Column |         Type          | Key? | Definition
+--------+-----------------------+------+------------
+ a      | integer               | yes  | a
+ b      | character varying(10) | yes  | b
+primary key, lsm, for table "public.cwi_test"
+
+CREATE UNIQUE INDEX cwi_uniq2_idx ON cwi_test(b , a);
+ALTER TABLE cwi_test DROP CONSTRAINT cwi_uniq_idx,
+	ADD CONSTRAINT cwi_replaced_pkey PRIMARY KEY
+		USING INDEX cwi_uniq2_idx;
+NOTICE:  ALTER TABLE / ADD CONSTRAINT USING INDEX will rename index "cwi_uniq2_idx" to "cwi_replaced_pkey"
+NOTICE:  table rewrite may lead to inconsistencies
+DETAIL:  Concurrent DMLs may not be reflected in the new table.
+HINT:  See https://github.com/yugabyte/yugabyte-db/issues/19860. Set 'ysql_suppress_unsafe_alter_notice' yb-tserver gflag to true to suppress this notice.
+\d cwi_test
+                     Table "public.cwi_test"
+ Column |         Type          | Collation | Nullable | Default
+--------+-----------------------+-----------+----------+---------
+ a      | integer               |           | not null |
+ b      | character varying(10) |           | not null |
+ c      | character(1)          |           |          |
+Indexes:
+    "cwi_replaced_pkey" PRIMARY KEY, lsm (b HASH, a ASC)
+
+\d cwi_replaced_pkey
+          Index "public.cwi_replaced_pkey"
+ Column |         Type          | Key? | Definition
+--------+-----------------------+------+------------
+ b      | character varying(10) | yes  | b
+ a      | integer               | yes  | a
+primary key, lsm, for table "public.cwi_test"
+
+DROP INDEX cwi_replaced_pkey;	-- Should fail; a constraint depends on it
+ERROR:  cannot drop index cwi_replaced_pkey because constraint cwi_replaced_pkey on table cwi_test requires it
+HINT:  You can drop constraint cwi_replaced_pkey on table cwi_test instead.
+DROP TABLE cwi_test;
+-- ADD CONSTRAINT USING INDEX is forbidden on partitioned tables
+CREATE TABLE cwi_test(a int) PARTITION BY hash (a);
+create unique index on cwi_test (a);
+alter table cwi_test add primary key using index cwi_test_a_idx ;
+ERROR:  ALTER TABLE / ADD CONSTRAINT USING INDEX is not supported on partitioned tables
+DROP TABLE cwi_test;
+--
 -- REINDEX (VERBOSE)
 --
 CREATE TABLE reindex_verbose(id integer primary key);

diff --git a/src/postgres/src/test/regress/expected/yb_pg_index_including.out b/src/postgres/src/test/regress/expected/yb_pg_index_including.out
@@ -82,16 +82,21 @@ WHERE i.indrelid = 'tbl_include_pk'::regclass ORDER BY c.relname;
  CREATE UNIQUE INDEX tbl_include_pk_pkey ON public.tbl_include_pk USING lsm (c1 HASH, c2 ASC) INCLUDE (c3, c4)
 (1 row)
 
--- NOT SUPPORTED
---
--- CREATE TABLE tbl_include_c4 (c1 int, c2 int, c3 int, c4 int);
--- INSERT INTO tbl_include_c4 SELECT 1, 2*x, 3*x, 4 FROM generate_series(1,10) AS x;
--- CREATE UNIQUE INDEX tbl_include_c4_idx_unique ON tbl_include_c4 using lsm (c1, c2) INCLUDE (c3, c4);
--- ALTER TABLE tbl_include_c4 add PRIMARY KEY USING INDEX tbl_include_c4_idx_unique;
--- SELECT pg_get_indexdef(i.indexrelid)
--- FROM pg_index i JOIN pg_class c ON i.indexrelid = c.oid
--- WHERE i.indrelid = 'tbl_include_c4'::regclass ORDER BY c.relname;
---
+CREATE TABLE tbl_include_c4 (c1 int, c2 int, c3 int, c4 int);
+INSERT INTO tbl_include_c4 SELECT 1, 2*x, 3*x, 4 FROM generate_series(1,10) AS x;
+CREATE UNIQUE INDEX tbl_include_c4_idx_unique ON tbl_include_c4 using lsm (c1, c2) INCLUDE (c3, c4);
+ALTER TABLE tbl_include_c4 add PRIMARY KEY USING INDEX tbl_include_c4_idx_unique;
+NOTICE:  table rewrite may lead to inconsistencies
+DETAIL:  Concurrent DMLs may not be reflected in the new table.
+HINT:  See https://github.com/yugabyte/yugabyte-db/issues/19860. Set 'ysql_suppress_unsafe_alter_notice' yb-tserver gflag to true to suppress this notice.
+SELECT pg_get_indexdef(i.indexrelid)
+FROM pg_index i JOIN pg_class c ON i.indexrelid = c.oid
+WHERE i.indrelid = 'tbl_include_c4'::regclass ORDER BY c.relname;
+                                                   pg_get_indexdef
+---------------------------------------------------------------------------------------------------------------------
+ CREATE UNIQUE INDEX tbl_include_c4_idx_unique ON public.tbl_include_c4 USING lsm (c1 HASH, c2 ASC) INCLUDE (c3, c4)
+(1 row)
+
 -- PK constraint. Must fail.
 CREATE TABLE tbl_include_c4_pk (c1 int, c2 int, c3 int, c4 int);
 INSERT INTO tbl_include_c4_pk SELECT 1, 2, 3*x, 4 FROM generate_series(1,10) AS x;

diff --git a/src/postgres/src/test/regress/sql/yb_alter_table_rewrite.sql b/src/postgres/src/test/regress/sql/yb_alter_table_rewrite.sql
@@ -138,6 +138,11 @@ SELECT col, col2, col4 FROM base ORDER BY col;
 \d+ base;
 SELECT num_tablets, num_hash_key_columns, is_colocated FROM
     yb_table_properties('base_idx'::regclass);
+CREATE UNIQUE INDEX base_idx_unique ON base(col);
+ALTER TABLE base ADD PRIMARY KEY USING INDEX base_idx_unique;
+INSERT INTO base VALUES (1, 1); -- should fail.
+INSERT INTO base VALUES (4, 4), (5, 5);
+SELECT col, col2 FROM base;
 CREATE TABLE base2 (col int, col2 int) WITH (COLOCATION=false);
 CREATE INDEX base2_idx ON base2(col2);
 INSERT INTO base2 VALUES (1, 3), (2, 2), (3, 1);
@@ -246,9 +251,29 @@ CREATE TYPE typeid AS (i int);
 CREATE TABLE nopk_udt (id typeid, v int);
 ALTER TABLE nopk_udt ADD PRIMARY KEY (id); -- should fail.
 -- test pk USING INDEX.
-CREATE TABLE nopk_usingindex (id int);
-CREATE UNIQUE INDEX nopk_idx ON nopk_usingindex (id ASC);
+CREATE TABLE nopk_usingindex (id int) SPLIT INTO 5 TABLETS;
+INSERT INTO nopk_usingindex VALUES (1), (2), (3);
+CREATE INDEX nopk_idx ON nopk_usingindex(id);
+CREATE UNIQUE INDEX nopk_idx2 ON nopk_usingindex (id HASH);
+CREATE UNIQUE INDEX nopk_idx3 ON nopk_usingindex (id ASC);
+CREATE UNIQUE INDEX nopk_idx4 ON nopk_usingindex (id DESC);
 ALTER TABLE nopk_usingindex ADD PRIMARY KEY USING INDEX nopk_idx; -- should fail.
+INSERT INTO nopk_usingindex VALUES (null);
+ALTER TABLE nopk_usingindex ADD PRIMARY KEY USING INDEX nopk_idx2; -- should fail.
+DELETE FROM nopk_usingindex WHERE id IS NULL;
+ALTER TABLE nopk_usingindex ADD PRIMARY KEY USING INDEX nopk_idx2;
+SELECT num_tablets, num_hash_key_columns FROM yb_table_properties('nopk_usingindex'::regclass);
+INSERT INTO nopk_usingindex VALUES (4);
+INSERT INTO nopk_usingindex VALUES (1); -- should fail.
+INSERT INTO nopk_usingindex VALUES (null); -- should fail.
+SELECT * FROM nopk_usingindex ORDER BY id;
+DROP INDEX nopk_idx2; -- should fail.
+ALTER TABLE nopk_usingindex DROP CONSTRAINT nopk_idx2;
+ALTER TABLE nopk_usingindex ADD PRIMARY KEY USING INDEX nopk_idx3;
+SELECT * FROM nopk_usingindex;
+DROP INDEX nopk_idx3; -- should fail.
+ALTER TABLE nopk_usingindex DROP CONSTRAINT nopk_idx3;
+ALTER TABLE nopk_usingindex ADD PRIMARY KEY USING INDEX nopk_idx4; -- should fail (not supported in PG).
 -- test adding/dropping pks on partitioned tables.
 CREATE TABLE nopk_whole (id int) PARTITION BY LIST (id);
 CREATE TABLE nopk_part1 PARTITION OF nopk_whole FOR VALUES IN (1, 2, 3);