Support automatically-updatable views.

This patch makes "simple" views automatically updatable, without the need
to create either INSTEAD OF triggers or INSTEAD rules.  "Simple" views
are those classified as updatable according to SQL-92 rules.  The rewriter
transforms INSERT/UPDATE/DELETE commands on such views directly into an
equivalent command on the underlying table, which will generally have
noticeably better performance than is possible with either triggers or
user-written rules.  A view that has INSTEAD OF triggers or INSTEAD rules
continues to operate the same as before.

For the moment, security_barrier views are not considered simple.
Also, we do not support WITH CHECK OPTION.  These features may be
added in future.

Dean Rasheed, reviewed by Amit Kapila

6 files changed, 1582 insertions, 22 deletions

diff --git a/src/test/regress/expected/triggers.out b/src/test/regress/expected/triggers.out
index 94ea61f80c..5140575f2a 100644
--- a/src/test/regress/expected/triggers.out
+++ b/src/test/regress/expected/triggers.out
@@ -820,20 +820,6 @@ DROP TABLE min_updates_test_oids;
 -- Test triggers on views
 --
 CREATE VIEW main_view AS SELECT a, b FROM main_table;
--- Updates should fail without rules or triggers
-INSERT INTO main_view VALUES (1,2);
-ERROR:  cannot insert into view "main_view"
-HINT:  You need an unconditional ON INSERT DO INSTEAD rule or an INSTEAD OF INSERT trigger.
-UPDATE main_view SET b = 20 WHERE a = 50;
-ERROR:  cannot update view "main_view"
-HINT:  You need an unconditional ON UPDATE DO INSTEAD rule or an INSTEAD OF UPDATE trigger.
-DELETE FROM main_view WHERE a = 50;
-ERROR:  cannot delete from view "main_view"
-HINT:  You need an unconditional ON DELETE DO INSTEAD rule or an INSTEAD OF DELETE trigger.
--- Should fail even when there are no matching rows
-DELETE FROM main_view WHERE a = 51;
-ERROR:  cannot delete from view "main_view"
-HINT:  You need an unconditional ON DELETE DO INSTEAD rule or an INSTEAD OF DELETE trigger.
 -- VIEW trigger function
 CREATE OR REPLACE FUNCTION view_trigger() RETURNS trigger
 LANGUAGE plpgsql AS $$
diff --git a/src/test/regress/expected/updatable_views.out b/src/test/regress/expected/updatable_views.out
new file mode 100644
index 0000000000..ead08d69b1
--- /dev/null
+++ b/src/test/regress/expected/updatable_views.out
@@ -0,0 +1,1069 @@
+--
+-- UPDATABLE VIEWS
+--
+-- check that non-updatable views are rejected with useful error messages
+CREATE TABLE base_tbl (a int PRIMARY KEY, b text DEFAULT 'Unspecified');
+INSERT INTO base_tbl SELECT i, 'Row ' || i FROM generate_series(-2, 2) g(i);
+CREATE VIEW ro_view1 AS SELECT DISTINCT a, b FROM base_tbl; -- DISTINCT not supported
+CREATE VIEW ro_view2 AS SELECT a, b FROM base_tbl GROUP BY a, b; -- GROUP BY not supported
+CREATE VIEW ro_view3 AS SELECT 1 FROM base_tbl HAVING max(a) > 0; -- HAVING not supported
+CREATE VIEW ro_view4 AS SELECT count(*) FROM base_tbl; -- Aggregate functions not supported
+CREATE VIEW ro_view5 AS SELECT a, rank() OVER() FROM base_tbl; -- Window functions not supported
+CREATE VIEW ro_view6 AS SELECT a, b FROM base_tbl UNION SELECT -a, b FROM base_tbl; -- Set ops not supported
+CREATE VIEW ro_view7 AS WITH t AS (SELECT a, b FROM base_tbl) SELECT * FROM t; -- WITH not supported
+CREATE VIEW ro_view8 AS SELECT a, b FROM base_tbl ORDER BY a OFFSET 1; -- OFFSET not supported
+CREATE VIEW ro_view9 AS SELECT a, b FROM base_tbl ORDER BY a LIMIT 1; -- LIMIT not supported
+CREATE VIEW ro_view10 AS SELECT 1 AS a; -- No base relations
+CREATE VIEW ro_view11 AS SELECT b1.a, b2.b FROM base_tbl b1, base_tbl b2; -- Multiple base relations
+CREATE VIEW ro_view12 AS SELECT * FROM generate_series(1, 10) AS g(a); -- SRF in rangetable
+CREATE VIEW ro_view13 AS SELECT a, b FROM (SELECT * FROM base_tbl) AS t; -- Subselect in rangetable
+CREATE VIEW ro_view14 AS SELECT ctid FROM base_tbl; -- System columns not supported
+CREATE VIEW ro_view15 AS SELECT a, upper(b) FROM base_tbl; -- Expression/function in targetlist
+CREATE VIEW ro_view16 AS SELECT a, b, a AS aa FROM base_tbl; -- Repeated column
+CREATE VIEW ro_view17 AS SELECT * FROM ro_view1; -- Base relation not updatable
+CREATE VIEW ro_view18 WITH (security_barrier = true)
+  AS SELECT * FROM base_tbl; -- Security barrier views not updatable
+CREATE VIEW ro_view19 AS SELECT * FROM (VALUES(1)) AS tmp(a); -- VALUES in rangetable
+CREATE SEQUENCE seq;
+CREATE VIEW ro_view20 AS SELECT * FROM seq; -- View based on a sequence
+SELECT table_name, is_insertable_into
+  FROM information_schema.tables
+ WHERE table_name LIKE 'ro_view%'
+ ORDER BY table_name;
+ table_name | is_insertable_into 
+------------+--------------------
+ ro_view1   | NO
+ ro_view10  | NO
+ ro_view11  | NO
+ ro_view12  | NO
+ ro_view13  | NO
+ ro_view14  | NO
+ ro_view15  | NO
+ ro_view16  | NO
+ ro_view17  | NO
+ ro_view18  | NO
+ ro_view19  | NO
+ ro_view2   | NO
+ ro_view20  | NO
+ ro_view3   | NO
+ ro_view4   | NO
+ ro_view5   | NO
+ ro_view6   | NO
+ ro_view7   | NO
+ ro_view8   | NO
+ ro_view9   | NO
+(20 rows)
+
+SELECT table_name, is_updatable, is_insertable_into
+  FROM information_schema.views
+ WHERE table_name LIKE 'ro_view%'
+ ORDER BY table_name;
+ table_name | is_updatable | is_insertable_into 
+------------+--------------+--------------------
+ ro_view1   | NO           | NO
+ ro_view10  | NO           | NO
+ ro_view11  | NO           | NO
+ ro_view12  | NO           | NO
+ ro_view13  | NO           | NO
+ ro_view14  | NO           | NO
+ ro_view15  | NO           | NO
+ ro_view16  | NO           | NO
+ ro_view17  | NO           | NO
+ ro_view18  | NO           | NO
+ ro_view19  | NO           | NO
+ ro_view2   | NO           | NO
+ ro_view20  | NO           | NO
+ ro_view3   | NO           | NO
+ ro_view4   | NO           | NO
+ ro_view5   | NO           | NO
+ ro_view6   | NO           | NO
+ ro_view7   | NO           | NO
+ ro_view8   | NO           | NO
+ ro_view9   | NO           | NO
+(20 rows)
+
+SELECT table_name, column_name, is_updatable
+  FROM information_schema.columns
+ WHERE table_name LIKE 'ro_view%'
+ ORDER BY table_name, ordinal_position;
+ table_name |  column_name  | is_updatable 
+------------+---------------+--------------
+ ro_view1   | a             | NO
+ ro_view1   | b             | NO
+ ro_view10  | a             | NO
+ ro_view11  | a             | NO
+ ro_view11  | b             | NO
+ ro_view12  | a             | NO
+ ro_view13  | a             | NO
+ ro_view13  | b             | NO
+ ro_view14  | ctid          | NO
+ ro_view15  | a             | NO
+ ro_view15  | upper         | NO
+ ro_view16  | a             | NO
+ ro_view16  | b             | NO
+ ro_view16  | aa            | NO
+ ro_view17  | a             | NO
+ ro_view17  | b             | NO
+ ro_view18  | a             | NO
+ ro_view18  | b             | NO
+ ro_view19  | a             | NO
+ ro_view2   | a             | NO
+ ro_view2   | b             | NO
+ ro_view20  | sequence_name | NO
+ ro_view20  | last_value    | NO
+ ro_view20  | start_value   | NO
+ ro_view20  | increment_by  | NO
+ ro_view20  | max_value     | NO
+ ro_view20  | min_value     | NO
+ ro_view20  | cache_value   | NO
+ ro_view20  | log_cnt       | NO
+ ro_view20  | is_cycled     | NO
+ ro_view20  | is_called     | NO
+ ro_view3   | ?column?      | NO
+ ro_view4   | count         | NO
+ ro_view5   | a             | NO
+ ro_view5   | rank          | NO
+ ro_view6   | a             | NO
+ ro_view6   | b             | NO
+ ro_view7   | a             | NO
+ ro_view7   | b             | NO
+ ro_view8   | a             | NO
+ ro_view8   | b             | NO
+ ro_view9   | a             | NO
+ ro_view9   | b             | NO
+(43 rows)
+
+DELETE FROM ro_view1;
+ERROR:  cannot delete from view "ro_view1"
+DETAIL:  Views containing DISTINCT are not automatically updatable.
+HINT:  To make the view updatable, provide an unconditional ON DELETE DO INSTEAD rule or an INSTEAD OF DELETE trigger.
+DELETE FROM ro_view2;
+ERROR:  cannot delete from view "ro_view2"
+DETAIL:  Views containing GROUP BY are not automatically updatable.
+HINT:  To make the view updatable, provide an unconditional ON DELETE DO INSTEAD rule or an INSTEAD OF DELETE trigger.
+DELETE FROM ro_view3;
+ERROR:  cannot delete from view "ro_view3"
+DETAIL:  Views containing HAVING are not automatically updatable.
+HINT:  To make the view updatable, provide an unconditional ON DELETE DO INSTEAD rule or an INSTEAD OF DELETE trigger.
+DELETE FROM ro_view4;
+ERROR:  cannot delete from view "ro_view4"
+DETAIL:  Views that return columns that are not columns of their base relation are not automatically updatable.
+HINT:  To make the view updatable, provide an unconditional ON DELETE DO INSTEAD rule or an INSTEAD OF DELETE trigger.
+DELETE FROM ro_view5;
+ERROR:  cannot delete from view "ro_view5"
+DETAIL:  Views that return columns that are not columns of their base relation are not automatically updatable.
+HINT:  To make the view updatable, provide an unconditional ON DELETE DO INSTEAD rule or an INSTEAD OF DELETE trigger.
+DELETE FROM ro_view6;
+ERROR:  cannot delete from view "ro_view6"
+DETAIL:  Views containing UNION, INTERSECT or EXCEPT are not automatically updatable.
+HINT:  To make the view updatable, provide an unconditional ON DELETE DO INSTEAD rule or an INSTEAD OF DELETE trigger.
+UPDATE ro_view7 SET a=a+1;
+ERROR:  cannot update view "ro_view7"
+DETAIL:  Views containing WITH are not automatically updatable.
+HINT:  To make the view updatable, provide an unconditional ON UPDATE DO INSTEAD rule or an INSTEAD OF UPDATE trigger.
+UPDATE ro_view8 SET a=a+1;
+ERROR:  cannot update view "ro_view8"
+DETAIL:  Views containing LIMIT or OFFSET are not automatically updatable.
+HINT:  To make the view updatable, provide an unconditional ON UPDATE DO INSTEAD rule or an INSTEAD OF UPDATE trigger.
+UPDATE ro_view9 SET a=a+1;
+ERROR:  cannot update view "ro_view9"
+DETAIL:  Views containing LIMIT or OFFSET are not automatically updatable.
+HINT:  To make the view updatable, provide an unconditional ON UPDATE DO INSTEAD rule or an INSTEAD OF UPDATE trigger.
+UPDATE ro_view10 SET a=a+1;
+ERROR:  cannot update view "ro_view10"
+DETAIL:  Views that do not select from a single table or view are not automatically updatable.
+HINT:  To make the view updatable, provide an unconditional ON UPDATE DO INSTEAD rule or an INSTEAD OF UPDATE trigger.
+UPDATE ro_view11 SET a=a+1;
+ERROR:  cannot update view "ro_view11"
+DETAIL:  Views that do not select from a single table or view are not automatically updatable.
+HINT:  To make the view updatable, provide an unconditional ON UPDATE DO INSTEAD rule or an INSTEAD OF UPDATE trigger.
+UPDATE ro_view12 SET a=a+1;
+ERROR:  cannot update view "ro_view12"
+DETAIL:  Views that do not select from a single table or view are not automatically updatable.
+HINT:  To make the view updatable, provide an unconditional ON UPDATE DO INSTEAD rule or an INSTEAD OF UPDATE trigger.
+INSERT INTO ro_view13 VALUES (3, 'Row 3');
+ERROR:  cannot insert into view "ro_view13"
+DETAIL:  Views that do not select from a single table or view are not automatically updatable.
+HINT:  To make the view insertable, provide an unconditional ON INSERT DO INSTEAD rule or an INSTEAD OF INSERT trigger.
+INSERT INTO ro_view14 VALUES (null);
+ERROR:  cannot insert into view "ro_view14"
+DETAIL:  Views that return system columns are not automatically updatable.
+HINT:  To make the view insertable, provide an unconditional ON INSERT DO INSTEAD rule or an INSTEAD OF INSERT trigger.
+INSERT INTO ro_view15 VALUES (3, 'ROW 3');
+ERROR:  cannot insert into view "ro_view15"
+DETAIL:  Views that return columns that are not columns of their base relation are not automatically updatable.
+HINT:  To make the view insertable, provide an unconditional ON INSERT DO INSTEAD rule or an INSTEAD OF INSERT trigger.
+INSERT INTO ro_view16 VALUES (3, 'Row 3', 3);
+ERROR:  cannot insert into view "ro_view16"
+DETAIL:  Views that return the same column more than once are not automatically updatable.
+HINT:  To make the view insertable, provide an unconditional ON INSERT DO INSTEAD rule or an INSTEAD OF INSERT trigger.
+INSERT INTO ro_view17 VALUES (3, 'ROW 3');
+ERROR:  cannot insert into view "ro_view1"
+DETAIL:  Views containing DISTINCT are not automatically updatable.
+HINT:  To make the view insertable, provide an unconditional ON INSERT DO INSTEAD rule or an INSTEAD OF INSERT trigger.
+INSERT INTO ro_view18 VALUES (3, 'ROW 3');
+ERROR:  cannot insert into view "ro_view18"
+DETAIL:  Security-barrier views are not automatically updatable.
+HINT:  To make the view insertable, provide an unconditional ON INSERT DO INSTEAD rule or an INSTEAD OF INSERT trigger.
+DELETE FROM ro_view19;
+ERROR:  cannot delete from view "ro_view19"
+DETAIL:  Views that do not select from a single table or view are not automatically updatable.
+HINT:  To make the view updatable, provide an unconditional ON DELETE DO INSTEAD rule or an INSTEAD OF DELETE trigger.
+UPDATE ro_view20 SET max_value=1000;
+ERROR:  cannot update view "ro_view20"
+DETAIL:  Views that do not select from a single table or view are not automatically updatable.
+HINT:  To make the view updatable, provide an unconditional ON UPDATE DO INSTEAD rule or an INSTEAD OF UPDATE trigger.
+DROP TABLE base_tbl CASCADE;
+NOTICE:  drop cascades to 16 other objects
+DETAIL:  drop cascades to view ro_view1
+drop cascades to view ro_view17
+drop cascades to view ro_view2
+drop cascades to view ro_view3
+drop cascades to view ro_view5
+drop cascades to view ro_view6
+drop cascades to view ro_view7
+drop cascades to view ro_view8
+drop cascades to view ro_view9
+drop cascades to view ro_view11
+drop cascades to view ro_view13
+drop cascades to view ro_view15
+drop cascades to view ro_view16
+drop cascades to view ro_view18
+drop cascades to view ro_view4
+drop cascades to view ro_view14
+DROP VIEW ro_view10, ro_view12, ro_view19;
+DROP SEQUENCE seq CASCADE;
+NOTICE:  drop cascades to view ro_view20
+-- simple updatable view
+CREATE TABLE base_tbl (a int PRIMARY KEY, b text DEFAULT 'Unspecified');
+INSERT INTO base_tbl SELECT i, 'Row ' || i FROM generate_series(-2, 2) g(i);
+CREATE VIEW rw_view1 AS SELECT * FROM base_tbl WHERE a>0;
+SELECT table_name, is_insertable_into
+  FROM information_schema.tables
+ WHERE table_name = 'rw_view1';
+ table_name | is_insertable_into 
+------------+--------------------
+ rw_view1   | YES
+(1 row)
+
+SELECT table_name, is_updatable, is_insertable_into
+  FROM information_schema.views
+ WHERE table_name = 'rw_view1';
+ table_name | is_updatable | is_insertable_into 
+------------+--------------+--------------------
+ rw_view1   | YES          | YES
+(1 row)
+
+SELECT table_name, column_name, is_updatable
+  FROM information_schema.columns
+ WHERE table_name = 'rw_view1'
+ ORDER BY ordinal_position;
+ table_name | column_name | is_updatable 
+------------+-------------+--------------
+ rw_view1   | a           | YES
+ rw_view1   | b           | YES
+(2 rows)
+
+INSERT INTO rw_view1 VALUES (3, 'Row 3');
+INSERT INTO rw_view1 (a) VALUES (4);
+UPDATE rw_view1 SET a=5 WHERE a=4;
+DELETE FROM rw_view1 WHERE b='Row 2';
+SELECT * FROM base_tbl;
+ a  |      b      
+----+-------------
+ -2 | Row -2
+ -1 | Row -1
+  0 | Row 0
+  1 | Row 1
+  3 | Row 3
+  5 | Unspecified
+(6 rows)
+
+EXPLAIN (costs off) UPDATE rw_view1 SET a=6 WHERE a=5;
+                    QUERY PLAN                    
+--------------------------------------------------
+ Update on base_tbl
+   ->  Index Scan using base_tbl_pkey on base_tbl
+         Index Cond: ((a > 0) AND (a = 5))
+(3 rows)
+
+EXPLAIN (costs off) DELETE FROM rw_view1 WHERE a=5;
+                    QUERY PLAN                    
+--------------------------------------------------
+ Delete on base_tbl
+   ->  Index Scan using base_tbl_pkey on base_tbl
+         Index Cond: ((a > 0) AND (a = 5))
+(3 rows)
+
+DROP TABLE base_tbl CASCADE;
+NOTICE:  drop cascades to view rw_view1
+-- view on top of view
+CREATE TABLE base_tbl (a int PRIMARY KEY, b text DEFAULT 'Unspecified');
+INSERT INTO base_tbl SELECT i, 'Row ' || i FROM generate_series(-2, 2) g(i);
+CREATE VIEW rw_view1 AS SELECT b AS bb, a AS aa FROM base_tbl WHERE a>0;
+CREATE VIEW rw_view2 AS SELECT aa AS aaa, bb AS bbb FROM rw_view1 WHERE aa<10;
+SELECT table_name, is_insertable_into
+  FROM information_schema.tables
+ WHERE table_name = 'rw_view2';
+ table_name | is_insertable_into 
+------------+--------------------
+ rw_view2   | YES
+(1 row)
+
+SELECT table_name, is_updatable, is_insertable_into
+  FROM information_schema.views
+ WHERE table_name = 'rw_view2';
+ table_name | is_updatable | is_insertable_into 
+------------+--------------+--------------------
+ rw_view2   | YES          | YES
+(1 row)
+
+SELECT table_name, column_name, is_updatable
+  FROM information_schema.columns
+ WHERE table_name = 'rw_view2'
+ ORDER BY ordinal_position;
+ table_name | column_name | is_updatable 
+------------+-------------+--------------
+ rw_view2   | aaa         | YES
+ rw_view2   | bbb         | YES
+(2 rows)
+
+INSERT INTO rw_view2 VALUES (3, 'Row 3');
+INSERT INTO rw_view2 (aaa) VALUES (4);
+SELECT * FROM rw_view2;
+ aaa |     bbb     
+-----+-------------
+   1 | Row 1
+   2 | Row 2
+   3 | Row 3
+   4 | Unspecified
+(4 rows)
+
+UPDATE rw_view2 SET bbb='Row 4' WHERE aaa=4;
+DELETE FROM rw_view2 WHERE aaa=2;
+SELECT * FROM rw_view2;
+ aaa |  bbb  
+-----+-------
+   1 | Row 1
+   3 | Row 3
+   4 | Row 4
+(3 rows)
+
+EXPLAIN (costs off) UPDATE rw_view2 SET aaa=5 WHERE aaa=4;
+                       QUERY PLAN                       
+--------------------------------------------------------
+ Update on base_tbl
+   ->  Index Scan using base_tbl_pkey on base_tbl
+         Index Cond: ((a < 10) AND (a > 0) AND (a = 4))
+(3 rows)
+
+EXPLAIN (costs off) DELETE FROM rw_view2 WHERE aaa=4;
+                       QUERY PLAN                       
+--------------------------------------------------------
+ Delete on base_tbl
+   ->  Index Scan using base_tbl_pkey on base_tbl
+         Index Cond: ((a < 10) AND (a > 0) AND (a = 4))
+(3 rows)
+
+DROP TABLE base_tbl CASCADE;
+NOTICE:  drop cascades to 2 other objects
+DETAIL:  drop cascades to view rw_view1
+drop cascades to view rw_view2
+-- view on top of view with rules
+CREATE TABLE base_tbl (a int PRIMARY KEY, b text DEFAULT 'Unspecified');
+INSERT INTO base_tbl SELECT i, 'Row ' || i FROM generate_series(-2, 2) g(i);
+CREATE VIEW rw_view1 AS SELECT * FROM base_tbl WHERE a>0 OFFSET 0; -- not updatable without rules/triggers
+CREATE VIEW rw_view2 AS SELECT * FROM rw_view1 WHERE a<10;
+SELECT table_name, is_insertable_into
+  FROM information_schema.tables
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+ table_name | is_insertable_into 
+------------+--------------------
+ rw_view1   | NO
+ rw_view2   | NO
+(2 rows)
+
+SELECT table_name, is_updatable, is_insertable_into
+  FROM information_schema.views
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+ table_name | is_updatable | is_insertable_into 
+------------+--------------+--------------------
+ rw_view1   | NO           | NO
+ rw_view2   | NO           | NO
+(2 rows)
+
+SELECT table_name, column_name, is_updatable
+  FROM information_schema.columns
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name, ordinal_position;
+ table_name | column_name | is_updatable 
+------------+-------------+--------------
+ rw_view1   | a           | NO
+ rw_view1   | b           | NO
+ rw_view2   | a           | NO
+ rw_view2   | b           | NO
+(4 rows)
+
+CREATE RULE rw_view1_ins_rule AS ON INSERT TO rw_view1
+  DO INSTEAD INSERT INTO base_tbl VALUES (NEW.a, NEW.b) RETURNING *;
+SELECT table_name, is_insertable_into
+  FROM information_schema.tables
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+ table_name | is_insertable_into 
+------------+--------------------
+ rw_view1   | YES
+ rw_view2   | YES
+(2 rows)
+
+SELECT table_name, is_updatable, is_insertable_into
+  FROM information_schema.views
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+ table_name | is_updatable | is_insertable_into 
+------------+--------------+--------------------
+ rw_view1   | NO           | YES
+ rw_view2   | NO           | YES
+(2 rows)
+
+SELECT table_name, column_name, is_updatable
+  FROM information_schema.columns
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name, ordinal_position;
+ table_name | column_name | is_updatable 
+------------+-------------+--------------
+ rw_view1   | a           | NO
+ rw_view1   | b           | NO
+ rw_view2   | a           | NO
+ rw_view2   | b           | NO
+(4 rows)
+
+CREATE RULE rw_view1_upd_rule AS ON UPDATE TO rw_view1
+  DO INSTEAD UPDATE base_tbl SET b=NEW.b WHERE a=OLD.a RETURNING NEW.*;
+SELECT table_name, is_insertable_into
+  FROM information_schema.tables
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+ table_name | is_insertable_into 
+------------+--------------------
+ rw_view1   | YES
+ rw_view2   | YES
+(2 rows)
+
+SELECT table_name, is_updatable, is_insertable_into
+  FROM information_schema.views
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+ table_name | is_updatable | is_insertable_into 
+------------+--------------+--------------------
+ rw_view1   | NO           | YES
+ rw_view2   | NO           | YES
+(2 rows)
+
+SELECT table_name, column_name, is_updatable
+  FROM information_schema.columns
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name, ordinal_position;
+ table_name | column_name | is_updatable 
+------------+-------------+--------------
+ rw_view1   | a           | NO
+ rw_view1   | b           | NO
+ rw_view2   | a           | NO
+ rw_view2   | b           | NO
+(4 rows)
+
+CREATE RULE rw_view1_del_rule AS ON DELETE TO rw_view1
+  DO INSTEAD DELETE FROM base_tbl WHERE a=OLD.a RETURNING OLD.*;
+SELECT table_name, is_insertable_into
+  FROM information_schema.tables
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+ table_name | is_insertable_into 
+------------+--------------------
+ rw_view1   | YES
+ rw_view2   | YES
+(2 rows)
+
+SELECT table_name, is_updatable, is_insertable_into
+  FROM information_schema.views
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+ table_name | is_updatable | is_insertable_into 
+------------+--------------+--------------------
+ rw_view1   | YES          | YES
+ rw_view2   | YES          | YES
+(2 rows)
+
+SELECT table_name, column_name, is_updatable
+  FROM information_schema.columns
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name, ordinal_position;
+ table_name | column_name | is_updatable 
+------------+-------------+--------------
+ rw_view1   | a           | YES
+ rw_view1   | b           | YES
+ rw_view2   | a           | YES
+ rw_view2   | b           | YES
+(4 rows)
+
+INSERT INTO rw_view2 VALUES (3, 'Row 3') RETURNING *;
+ a |   b   
+---+-------
+ 3 | Row 3
+(1 row)
+
+UPDATE rw_view2 SET b='Row three' WHERE a=3 RETURNING *;
+ a |     b     
+---+-----------
+ 3 | Row three
+(1 row)
+
+SELECT * FROM rw_view2;
+ a |     b     
+---+-----------
+ 1 | Row 1
+ 2 | Row 2
+ 3 | Row three
+(3 rows)
+
+DELETE FROM rw_view2 WHERE a=3 RETURNING *;
+ a |     b     
+---+-----------
+ 3 | Row three
+(1 row)
+
+SELECT * FROM rw_view2;
+ a |   b   
+---+-------
+ 1 | Row 1
+ 2 | Row 2
+(2 rows)
+
+EXPLAIN (costs off) UPDATE rw_view2 SET a=3 WHERE a=2;
+                            QUERY PLAN                            
+------------------------------------------------------------------
+ Update on base_tbl
+   ->  Nested Loop
+         ->  Index Scan using base_tbl_pkey on base_tbl
+               Index Cond: (a = 2)
+         ->  Subquery Scan on rw_view1
+               Filter: ((rw_view1.a < 10) AND (rw_view1.a = 2))
+               ->  Limit
+                     ->  Bitmap Heap Scan on base_tbl base_tbl_1
+                           Recheck Cond: (a > 0)
+                           ->  Bitmap Index Scan on base_tbl_pkey
+                                 Index Cond: (a > 0)
+(11 rows)
+
+EXPLAIN (costs off) DELETE FROM rw_view2 WHERE a=2;
+                            QUERY PLAN                            
+------------------------------------------------------------------
+ Delete on base_tbl
+   ->  Nested Loop
+         ->  Index Scan using base_tbl_pkey on base_tbl
+               Index Cond: (a = 2)
+         ->  Subquery Scan on rw_view1
+               Filter: ((rw_view1.a < 10) AND (rw_view1.a = 2))
+               ->  Limit
+                     ->  Bitmap Heap Scan on base_tbl base_tbl_1
+                           Recheck Cond: (a > 0)
+                           ->  Bitmap Index Scan on base_tbl_pkey
+                                 Index Cond: (a > 0)
+(11 rows)
+
+DROP TABLE base_tbl CASCADE;
+NOTICE:  drop cascades to 2 other objects
+DETAIL:  drop cascades to view rw_view1
+drop cascades to view rw_view2
+-- view on top of view with triggers
+CREATE TABLE base_tbl (a int PRIMARY KEY, b text DEFAULT 'Unspecified');
+INSERT INTO base_tbl SELECT i, 'Row ' || i FROM generate_series(-2, 2) g(i);
+CREATE VIEW rw_view1 AS SELECT * FROM base_tbl WHERE a>0 OFFSET 0; -- not updatable without rules/triggers
+CREATE VIEW rw_view2 AS SELECT * FROM rw_view1 WHERE a<10;
+SELECT table_name, is_insertable_into
+  FROM information_schema.tables
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+ table_name | is_insertable_into 
+------------+--------------------
+ rw_view1   | NO
+ rw_view2   | NO
+(2 rows)
+
+SELECT table_name, is_updatable, is_insertable_into,
+       is_trigger_updatable, is_trigger_deletable,
+       is_trigger_insertable_into
+  FROM information_schema.views
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+ table_name | is_updatable | is_insertable_into | is_trigger_updatable | is_trigger_deletable | is_trigger_insertable_into 
+------------+--------------+--------------------+----------------------+----------------------+----------------------------
+ rw_view1   | NO           | NO                 | NO                   | NO                   | NO
+ rw_view2   | NO           | NO                 | NO                   | NO                   | NO
+(2 rows)
+
+SELECT table_name, column_name, is_updatable
+  FROM information_schema.columns
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name, ordinal_position;
+ table_name | column_name | is_updatable 
+------------+-------------+--------------
+ rw_view1   | a           | NO
+ rw_view1   | b           | NO
+ rw_view2   | a           | NO
+ rw_view2   | b           | NO
+(4 rows)
+
+CREATE FUNCTION rw_view1_trig_fn()
+RETURNS trigger AS
+$$
+BEGIN
+  IF TG_OP = 'INSERT' THEN
+    INSERT INTO base_tbl VALUES (NEW.a, NEW.b);
+    RETURN NEW;
+  ELSIF TG_OP = 'UPDATE' THEN
+    UPDATE base_tbl SET b=NEW.b WHERE a=OLD.a;
+    RETURN NEW;
+  ELSIF TG_OP = 'DELETE' THEN
+    DELETE FROM base_tbl WHERE a=OLD.a;
+    RETURN OLD;
+  END IF;
+END;
+$$
+LANGUAGE plpgsql;
+CREATE TRIGGER rw_view1_ins_trig INSTEAD OF INSERT ON rw_view1
+  FOR EACH ROW EXECUTE PROCEDURE rw_view1_trig_fn();
+SELECT table_name, is_insertable_into
+  FROM information_schema.tables
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+ table_name | is_insertable_into 
+------------+--------------------
+ rw_view1   | NO
+ rw_view2   | NO
+(2 rows)
+
+SELECT table_name, is_updatable, is_insertable_into,
+       is_trigger_updatable, is_trigger_deletable,
+       is_trigger_insertable_into
+  FROM information_schema.views
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+ table_name | is_updatable | is_insertable_into | is_trigger_updatable | is_trigger_deletable | is_trigger_insertable_into 
+------------+--------------+--------------------+----------------------+----------------------+----------------------------
+ rw_view1   | NO           | NO                 | NO                   | NO                   | YES
+ rw_view2   | NO           | NO                 | NO                   | NO                   | NO
+(2 rows)
+
+SELECT table_name, column_name, is_updatable
+  FROM information_schema.columns
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name, ordinal_position;
+ table_name | column_name | is_updatable 
+------------+-------------+--------------
+ rw_view1   | a           | NO
+ rw_view1   | b           | NO
+ rw_view2   | a           | NO
+ rw_view2   | b           | NO
+(4 rows)
+
+CREATE TRIGGER rw_view1_upd_trig INSTEAD OF UPDATE ON rw_view1
+  FOR EACH ROW EXECUTE PROCEDURE rw_view1_trig_fn();
+SELECT table_name, is_insertable_into
+  FROM information_schema.tables
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+ table_name | is_insertable_into 
+------------+--------------------
+ rw_view1   | NO
+ rw_view2   | NO
+(2 rows)
+
+SELECT table_name, is_updatable, is_insertable_into,
+       is_trigger_updatable, is_trigger_deletable,
+       is_trigger_insertable_into
+  FROM information_schema.views
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+ table_name | is_updatable | is_insertable_into | is_trigger_updatable | is_trigger_deletable | is_trigger_insertable_into 
+------------+--------------+--------------------+----------------------+----------------------+----------------------------
+ rw_view1   | NO           | NO                 | YES                  | NO                   | YES
+ rw_view2   | NO           | NO                 | NO                   | NO                   | NO
+(2 rows)
+
+SELECT table_name, column_name, is_updatable
+  FROM information_schema.columns
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name, ordinal_position;
+ table_name | column_name | is_updatable 
+------------+-------------+--------------
+ rw_view1   | a           | NO
+ rw_view1   | b           | NO
+ rw_view2   | a           | NO
+ rw_view2   | b           | NO
+(4 rows)
+
+CREATE TRIGGER rw_view1_del_trig INSTEAD OF DELETE ON rw_view1
+  FOR EACH ROW EXECUTE PROCEDURE rw_view1_trig_fn();
+SELECT table_name, is_insertable_into
+  FROM information_schema.tables
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+ table_name | is_insertable_into 
+------------+--------------------
+ rw_view1   | NO
+ rw_view2   | NO
+(2 rows)
+
+SELECT table_name, is_updatable, is_insertable_into,
+       is_trigger_updatable, is_trigger_deletable,
+       is_trigger_insertable_into
+  FROM information_schema.views
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+ table_name | is_updatable | is_insertable_into | is_trigger_updatable | is_trigger_deletable | is_trigger_insertable_into 
+------------+--------------+--------------------+----------------------+----------------------+----------------------------
+ rw_view1   | NO           | NO                 | YES                  | YES                  | YES
+ rw_view2   | NO           | NO                 | NO                   | NO                   | NO
+(2 rows)
+
+SELECT table_name, column_name, is_updatable
+  FROM information_schema.columns
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name, ordinal_position;
+ table_name | column_name | is_updatable 
+------------+-------------+--------------
+ rw_view1   | a           | NO
+ rw_view1   | b           | NO
+ rw_view2   | a           | NO
+ rw_view2   | b           | NO
+(4 rows)
+
+INSERT INTO rw_view2 VALUES (3, 'Row 3') RETURNING *;
+ a |   b   
+---+-------
+ 3 | Row 3
+(1 row)
+
+UPDATE rw_view2 SET b='Row three' WHERE a=3 RETURNING *;
+ a |     b     
+---+-----------
+ 3 | Row three
+(1 row)
+
+SELECT * FROM rw_view2;
+ a |     b     
+---+-----------
+ 1 | Row 1
+ 2 | Row 2
+ 3 | Row three
+(3 rows)
+
+DELETE FROM rw_view2 WHERE a=3 RETURNING *;
+ a |     b     
+---+-----------
+ 3 | Row three
+(1 row)
+
+SELECT * FROM rw_view2;
+ a |   b   
+---+-------
+ 1 | Row 1
+ 2 | Row 2
+(2 rows)
+
+EXPLAIN (costs off) UPDATE rw_view2 SET a=3 WHERE a=2;
+                         QUERY PLAN                         
+------------------------------------------------------------
+ Update on rw_view1 rw_view1_1
+   ->  Subquery Scan on rw_view1
+         Filter: ((rw_view1.a < 10) AND (rw_view1.a = 2))
+         ->  Limit
+               ->  Bitmap Heap Scan on base_tbl
+                     Recheck Cond: (a > 0)
+                     ->  Bitmap Index Scan on base_tbl_pkey
+                           Index Cond: (a > 0)
+(8 rows)
+
+EXPLAIN (costs off) DELETE FROM rw_view2 WHERE a=2;
+                         QUERY PLAN                         
+------------------------------------------------------------
+ Delete on rw_view1 rw_view1_1
+   ->  Subquery Scan on rw_view1
+         Filter: ((rw_view1.a < 10) AND (rw_view1.a = 2))
+         ->  Limit
+               ->  Bitmap Heap Scan on base_tbl
+                     Recheck Cond: (a > 0)
+                     ->  Bitmap Index Scan on base_tbl_pkey
+                           Index Cond: (a > 0)
+(8 rows)
+
+DROP TABLE base_tbl CASCADE;
+NOTICE:  drop cascades to 2 other objects
+DETAIL:  drop cascades to view rw_view1
+drop cascades to view rw_view2
+DROP FUNCTION rw_view1_trig_fn();
+-- update using whole row from view
+CREATE TABLE base_tbl (a int PRIMARY KEY, b text DEFAULT 'Unspecified');
+INSERT INTO base_tbl SELECT i, 'Row ' || i FROM generate_series(-2, 2) g(i);
+CREATE VIEW rw_view1 AS SELECT b AS bb, a AS aa FROM base_tbl;
+CREATE FUNCTION rw_view1_aa(x rw_view1)
+  RETURNS int AS $$ SELECT x.aa $$ LANGUAGE sql;
+UPDATE rw_view1 v SET bb='Updated row 2' WHERE rw_view1_aa(v)=2
+  RETURNING rw_view1_aa(v), v.bb;
+ rw_view1_aa |      bb       
+-------------+---------------
+           2 | Updated row 2
+(1 row)
+
+SELECT * FROM base_tbl;
+ a  |       b       
+----+---------------
+ -2 | Row -2
+ -1 | Row -1
+  0 | Row 0
+  1 | Row 1
+  2 | Updated row 2
+(5 rows)
+
+EXPLAIN (costs off)
+UPDATE rw_view1 v SET bb='Updated row 2' WHERE rw_view1_aa(v)=2
+  RETURNING rw_view1_aa(v), v.bb;
+                    QUERY PLAN                    
+--------------------------------------------------
+ Update on base_tbl
+   ->  Index Scan using base_tbl_pkey on base_tbl
+         Index Cond: (a = 2)
+(3 rows)
+
+DROP TABLE base_tbl CASCADE;
+NOTICE:  drop cascades to 2 other objects
+DETAIL:  drop cascades to view rw_view1
+drop cascades to function rw_view1_aa(rw_view1)
+-- permissions checks
+CREATE USER view_user1;
+CREATE USER view_user2;
+SET SESSION AUTHORIZATION view_user1;
+CREATE TABLE base_tbl(a int, b text, c float);
+INSERT INTO base_tbl VALUES (1, 'Row 1', 1.0);
+CREATE VIEW rw_view1 AS SELECT b AS bb, c AS cc, a AS aa FROM base_tbl;
+INSERT INTO rw_view1 VALUES ('Row 2', 2.0, 2);
+GRANT SELECT ON base_tbl TO view_user2;
+GRANT SELECT ON rw_view1 TO view_user2;
+GRANT UPDATE (a,c) ON base_tbl TO view_user2;
+GRANT UPDATE (bb,cc) ON rw_view1 TO view_user2;
+RESET SESSION AUTHORIZATION;
+SET SESSION AUTHORIZATION view_user2;
+CREATE VIEW rw_view2 AS SELECT b AS bb, c AS cc, a AS aa FROM base_tbl;
+SELECT * FROM base_tbl; -- ok
+ a |   b   | c 
+---+-------+---
+ 1 | Row 1 | 1
+ 2 | Row 2 | 2
+(2 rows)
+
+SELECT * FROM rw_view1; -- ok
+  bb   | cc | aa 
+-------+----+----
+ Row 1 |  1 |  1
+ Row 2 |  2 |  2
+(2 rows)
+
+SELECT * FROM rw_view2; -- ok
+  bb   | cc | aa 
+-------+----+----
+ Row 1 |  1 |  1
+ Row 2 |  2 |  2
+(2 rows)
+
+INSERT INTO base_tbl VALUES (3, 'Row 3', 3.0); -- not allowed
+ERROR:  permission denied for relation base_tbl
+INSERT INTO rw_view1 VALUES ('Row 3', 3.0, 3); -- not allowed
+ERROR:  permission denied for relation rw_view1
+INSERT INTO rw_view2 VALUES ('Row 3', 3.0, 3); -- not allowed
+ERROR:  permission denied for relation base_tbl
+UPDATE base_tbl SET a=a, c=c; -- ok
+UPDATE base_tbl SET b=b; -- not allowed
+ERROR:  permission denied for relation base_tbl
+UPDATE rw_view1 SET bb=bb, cc=cc; -- ok
+UPDATE rw_view1 SET aa=aa; -- not allowed
+ERROR:  permission denied for relation rw_view1
+UPDATE rw_view2 SET aa=aa, cc=cc; -- ok
+UPDATE rw_view2 SET bb=bb; -- not allowed
+ERROR:  permission denied for relation base_tbl
+DELETE FROM base_tbl; -- not allowed
+ERROR:  permission denied for relation base_tbl
+DELETE FROM rw_view1; -- not allowed
+ERROR:  permission denied for relation rw_view1
+DELETE FROM rw_view2; -- not allowed
+ERROR:  permission denied for relation base_tbl
+RESET SESSION AUTHORIZATION;
+SET SESSION AUTHORIZATION view_user1;
+GRANT INSERT, DELETE ON base_tbl TO view_user2;
+RESET SESSION AUTHORIZATION;
+SET SESSION AUTHORIZATION view_user2;
+INSERT INTO base_tbl VALUES (3, 'Row 3', 3.0); -- ok
+INSERT INTO rw_view1 VALUES ('Row 4', 4.0, 4); -- not allowed
+ERROR:  permission denied for relation rw_view1
+INSERT INTO rw_view2 VALUES ('Row 4', 4.0, 4); -- ok
+DELETE FROM base_tbl WHERE a=1; -- ok
+DELETE FROM rw_view1 WHERE aa=2; -- not allowed
+ERROR:  permission denied for relation rw_view1
+DELETE FROM rw_view2 WHERE aa=2; -- ok
+SELECT * FROM base_tbl;
+ a |   b   | c 
+---+-------+---
+ 3 | Row 3 | 3
+ 4 | Row 4 | 4
+(2 rows)
+
+RESET SESSION AUTHORIZATION;
+SET SESSION AUTHORIZATION view_user1;
+REVOKE INSERT, DELETE ON base_tbl FROM view_user2;
+GRANT INSERT, DELETE ON rw_view1 TO view_user2;
+RESET SESSION AUTHORIZATION;
+SET SESSION AUTHORIZATION view_user2;
+INSERT INTO base_tbl VALUES (5, 'Row 5', 5.0); -- not allowed
+ERROR:  permission denied for relation base_tbl
+INSERT INTO rw_view1 VALUES ('Row 5', 5.0, 5); -- ok
+INSERT INTO rw_view2 VALUES ('Row 6', 6.0, 6); -- not allowed
+ERROR:  permission denied for relation base_tbl
+DELETE FROM base_tbl WHERE a=3; -- not allowed
+ERROR:  permission denied for relation base_tbl
+DELETE FROM rw_view1 WHERE aa=3; -- ok
+DELETE FROM rw_view2 WHERE aa=4; -- not allowed
+ERROR:  permission denied for relation base_tbl
+SELECT * FROM base_tbl;
+ a |   b   | c 
+---+-------+---
+ 4 | Row 4 | 4
+ 5 | Row 5 | 5
+(2 rows)
+
+RESET SESSION AUTHORIZATION;
+DROP TABLE base_tbl CASCADE;
+NOTICE:  drop cascades to 2 other objects
+DETAIL:  drop cascades to view rw_view1
+drop cascades to view rw_view2
+DROP USER view_user1;
+DROP USER view_user2;
+-- column defaults
+CREATE TABLE base_tbl (a int PRIMARY KEY, b text DEFAULT 'Unspecified', c serial);
+INSERT INTO base_tbl VALUES (1, 'Row 1');
+INSERT INTO base_tbl VALUES (2, 'Row 2');
+INSERT INTO base_tbl VALUES (3);
+CREATE VIEW rw_view1 AS SELECT a AS aa, b AS bb FROM base_tbl;
+ALTER VIEW rw_view1 ALTER COLUMN bb SET DEFAULT 'View default';
+INSERT INTO rw_view1 VALUES (4, 'Row 4');
+INSERT INTO rw_view1 (aa) VALUES (5);
+SELECT * FROM base_tbl;
+ a |      b       | c 
+---+--------------+---
+ 1 | Row 1        | 1
+ 2 | Row 2        | 2
+ 3 | Unspecified  | 3
+ 4 | Row 4        | 4
+ 5 | View default | 5
+(5 rows)
+
+DROP TABLE base_tbl CASCADE;
+NOTICE:  drop cascades to view rw_view1
+-- Table having triggers
+CREATE TABLE base_tbl (a int PRIMARY KEY, b text DEFAULT 'Unspecified');
+INSERT INTO base_tbl VALUES (1, 'Row 1');
+INSERT INTO base_tbl VALUES (2, 'Row 2');
+CREATE FUNCTION rw_view1_trig_fn()
+RETURNS trigger AS
+$$
+BEGIN
+  IF TG_OP = 'INSERT' THEN
+    UPDATE base_tbl SET b=NEW.b WHERE a=1;
+    RETURN NULL;
+  END IF;
+  RETURN NULL;
+END;
+$$
+LANGUAGE plpgsql;
+CREATE TRIGGER rw_view1_ins_trig AFTER INSERT ON base_tbl
+  FOR EACH ROW EXECUTE PROCEDURE rw_view1_trig_fn();
+CREATE VIEW rw_view1 AS SELECT a AS aa, b AS bb FROM base_tbl;
+INSERT INTO rw_view1 VALUES (3, 'Row 3');
+select * from base_tbl;
+ a |   b   
+---+-------
+ 2 | Row 2
+ 3 | Row 3
+ 1 | Row 3
+(3 rows)
+
+DROP VIEW rw_view1;
+DROP TRIGGER rw_view1_ins_trig on base_tbl;
+DROP FUNCTION rw_view1_trig_fn();
+DROP TABLE base_tbl;
+-- view with ORDER BY
+CREATE TABLE base_tbl (a int, b int);
+INSERT INTO base_tbl VALUES (1,2), (4,5), (3,-3);
+CREATE VIEW rw_view1 AS SELECT * FROM base_tbl ORDER BY a+b;
+SELECT * FROM rw_view1;
+ a | b  
+---+----
+ 3 | -3
+ 1 |  2
+ 4 |  5
+(3 rows)
+
+INSERT INTO rw_view1 VALUES (7,-8);
+SELECT * FROM rw_view1;
+ a | b  
+---+----
+ 7 | -8
+ 3 | -3
+ 1 |  2
+ 4 |  5
+(4 rows)
+
+EXPLAIN (verbose, costs off) UPDATE rw_view1 SET b = b + 1 RETURNING *;
+                         QUERY PLAN                          
+-------------------------------------------------------------
+ Update on public.base_tbl
+   Output: base_tbl.a, base_tbl.b
+   ->  Seq Scan on public.base_tbl
+         Output: base_tbl.a, (base_tbl.b + 1), base_tbl.ctid
+(4 rows)
+
+UPDATE rw_view1 SET b = b + 1 RETURNING *;
+ a | b  
+---+----
+ 1 |  3
+ 4 |  6
+ 3 | -2
+ 7 | -7
+(4 rows)
+
+SELECT * FROM rw_view1;
+ a | b  
+---+----
+ 7 | -7
+ 3 | -2
+ 1 |  3
+ 4 |  6
+(4 rows)
+
+DROP TABLE base_tbl CASCADE;
+NOTICE:  drop cascades to view rw_view1
+-- multiple array-column updates
+CREATE TABLE base_tbl (a int, arr int[]);
+INSERT INTO base_tbl VALUES (1,ARRAY[2]), (3,ARRAY[4]);
+CREATE VIEW rw_view1 AS SELECT * FROM base_tbl;
+UPDATE rw_view1 SET arr[1] = 42, arr[2] = 77 WHERE a = 3;
+SELECT * FROM rw_view1;
+ a |   arr   
+---+---------
+ 1 | {2}
+ 3 | {42,77}
+(2 rows)
+
+DROP TABLE base_tbl CASCADE;
+NOTICE:  drop cascades to view rw_view1
diff --git a/src/test/regress/parallel_schedule b/src/test/regress/parallel_schedule
index 663bf8ac56..bdcf3a6a55 100644
--- a/src/test/regress/parallel_schedule
+++ b/src/test/regress/parallel_schedule
@@ -59,7 +59,7 @@ test: create_index create_view
 # ----------
 # Another group of parallel tests
 # ----------
-test: create_aggregate create_function_3 create_cast constraints triggers inherit create_table_like typed_table vacuum drop_if_exists
+test: create_aggregate create_function_3 create_cast constraints triggers inherit create_table_like typed_table vacuum drop_if_exists updatable_views
 
 # ----------
 # sanity_check does a vacuum, affecting the sort order of SELECT *
diff --git a/src/test/regress/serial_schedule b/src/test/regress/serial_schedule
index be789e3f44..c7c2ed0f6a 100644
--- a/src/test/regress/serial_schedule
+++ b/src/test/regress/serial_schedule
@@ -67,6 +67,7 @@ test: create_table_like
 test: typed_table
 test: vacuum
 test: drop_if_exists
+test: updatable_views
 test: sanity_check
 test: errors
 test: select
diff --git a/src/test/regress/sql/triggers.sql b/src/test/regress/sql/triggers.sql
index 78c5407560..0ea2c314de 100644
--- a/src/test/regress/sql/triggers.sql
+++ b/src/test/regress/sql/triggers.sql
@@ -611,13 +611,6 @@ DROP TABLE min_updates_test_oids;
 
 CREATE VIEW main_view AS SELECT a, b FROM main_table;
 
--- Updates should fail without rules or triggers
-INSERT INTO main_view VALUES (1,2);
-UPDATE main_view SET b = 20 WHERE a = 50;
-DELETE FROM main_view WHERE a = 50;
--- Should fail even when there are no matching rows
-DELETE FROM main_view WHERE a = 51;
-
 -- VIEW trigger function
 CREATE OR REPLACE FUNCTION view_trigger() RETURNS trigger
 LANGUAGE plpgsql AS $$
diff --git a/src/test/regress/sql/updatable_views.sql b/src/test/regress/sql/updatable_views.sql
new file mode 100644
index 0000000000..49dfedd3a6
--- /dev/null
+++ b/src/test/regress/sql/updatable_views.sql
@@ -0,0 +1,511 @@
+--
+-- UPDATABLE VIEWS
+--
+
+-- check that non-updatable views are rejected with useful error messages
+
+CREATE TABLE base_tbl (a int PRIMARY KEY, b text DEFAULT 'Unspecified');
+INSERT INTO base_tbl SELECT i, 'Row ' || i FROM generate_series(-2, 2) g(i);
+
+CREATE VIEW ro_view1 AS SELECT DISTINCT a, b FROM base_tbl; -- DISTINCT not supported
+CREATE VIEW ro_view2 AS SELECT a, b FROM base_tbl GROUP BY a, b; -- GROUP BY not supported
+CREATE VIEW ro_view3 AS SELECT 1 FROM base_tbl HAVING max(a) > 0; -- HAVING not supported
+CREATE VIEW ro_view4 AS SELECT count(*) FROM base_tbl; -- Aggregate functions not supported
+CREATE VIEW ro_view5 AS SELECT a, rank() OVER() FROM base_tbl; -- Window functions not supported
+CREATE VIEW ro_view6 AS SELECT a, b FROM base_tbl UNION SELECT -a, b FROM base_tbl; -- Set ops not supported
+CREATE VIEW ro_view7 AS WITH t AS (SELECT a, b FROM base_tbl) SELECT * FROM t; -- WITH not supported
+CREATE VIEW ro_view8 AS SELECT a, b FROM base_tbl ORDER BY a OFFSET 1; -- OFFSET not supported
+CREATE VIEW ro_view9 AS SELECT a, b FROM base_tbl ORDER BY a LIMIT 1; -- LIMIT not supported
+CREATE VIEW ro_view10 AS SELECT 1 AS a; -- No base relations
+CREATE VIEW ro_view11 AS SELECT b1.a, b2.b FROM base_tbl b1, base_tbl b2; -- Multiple base relations
+CREATE VIEW ro_view12 AS SELECT * FROM generate_series(1, 10) AS g(a); -- SRF in rangetable
+CREATE VIEW ro_view13 AS SELECT a, b FROM (SELECT * FROM base_tbl) AS t; -- Subselect in rangetable
+CREATE VIEW ro_view14 AS SELECT ctid FROM base_tbl; -- System columns not supported
+CREATE VIEW ro_view15 AS SELECT a, upper(b) FROM base_tbl; -- Expression/function in targetlist
+CREATE VIEW ro_view16 AS SELECT a, b, a AS aa FROM base_tbl; -- Repeated column
+CREATE VIEW ro_view17 AS SELECT * FROM ro_view1; -- Base relation not updatable
+CREATE VIEW ro_view18 WITH (security_barrier = true)
+  AS SELECT * FROM base_tbl; -- Security barrier views not updatable
+CREATE VIEW ro_view19 AS SELECT * FROM (VALUES(1)) AS tmp(a); -- VALUES in rangetable
+CREATE SEQUENCE seq;
+CREATE VIEW ro_view20 AS SELECT * FROM seq; -- View based on a sequence
+
+SELECT table_name, is_insertable_into
+  FROM information_schema.tables
+ WHERE table_name LIKE 'ro_view%'
+ ORDER BY table_name;
+
+SELECT table_name, is_updatable, is_insertable_into
+  FROM information_schema.views
+ WHERE table_name LIKE 'ro_view%'
+ ORDER BY table_name;
+
+SELECT table_name, column_name, is_updatable
+  FROM information_schema.columns
+ WHERE table_name LIKE 'ro_view%'
+ ORDER BY table_name, ordinal_position;
+
+DELETE FROM ro_view1;
+DELETE FROM ro_view2;
+DELETE FROM ro_view3;
+DELETE FROM ro_view4;
+DELETE FROM ro_view5;
+DELETE FROM ro_view6;
+UPDATE ro_view7 SET a=a+1;
+UPDATE ro_view8 SET a=a+1;
+UPDATE ro_view9 SET a=a+1;
+UPDATE ro_view10 SET a=a+1;
+UPDATE ro_view11 SET a=a+1;
+UPDATE ro_view12 SET a=a+1;
+INSERT INTO ro_view13 VALUES (3, 'Row 3');
+INSERT INTO ro_view14 VALUES (null);
+INSERT INTO ro_view15 VALUES (3, 'ROW 3');
+INSERT INTO ro_view16 VALUES (3, 'Row 3', 3);
+INSERT INTO ro_view17 VALUES (3, 'ROW 3');
+INSERT INTO ro_view18 VALUES (3, 'ROW 3');
+DELETE FROM ro_view19;
+UPDATE ro_view20 SET max_value=1000;
+
+DROP TABLE base_tbl CASCADE;
+DROP VIEW ro_view10, ro_view12, ro_view19;
+DROP SEQUENCE seq CASCADE;
+
+-- simple updatable view
+
+CREATE TABLE base_tbl (a int PRIMARY KEY, b text DEFAULT 'Unspecified');
+INSERT INTO base_tbl SELECT i, 'Row ' || i FROM generate_series(-2, 2) g(i);
+
+CREATE VIEW rw_view1 AS SELECT * FROM base_tbl WHERE a>0;
+
+SELECT table_name, is_insertable_into
+  FROM information_schema.tables
+ WHERE table_name = 'rw_view1';
+
+SELECT table_name, is_updatable, is_insertable_into
+  FROM information_schema.views
+ WHERE table_name = 'rw_view1';
+
+SELECT table_name, column_name, is_updatable
+  FROM information_schema.columns
+ WHERE table_name = 'rw_view1'
+ ORDER BY ordinal_position;
+
+INSERT INTO rw_view1 VALUES (3, 'Row 3');
+INSERT INTO rw_view1 (a) VALUES (4);
+UPDATE rw_view1 SET a=5 WHERE a=4;
+DELETE FROM rw_view1 WHERE b='Row 2';
+SELECT * FROM base_tbl;
+
+EXPLAIN (costs off) UPDATE rw_view1 SET a=6 WHERE a=5;
+EXPLAIN (costs off) DELETE FROM rw_view1 WHERE a=5;
+
+DROP TABLE base_tbl CASCADE;
+
+-- view on top of view
+
+CREATE TABLE base_tbl (a int PRIMARY KEY, b text DEFAULT 'Unspecified');
+INSERT INTO base_tbl SELECT i, 'Row ' || i FROM generate_series(-2, 2) g(i);
+
+CREATE VIEW rw_view1 AS SELECT b AS bb, a AS aa FROM base_tbl WHERE a>0;
+CREATE VIEW rw_view2 AS SELECT aa AS aaa, bb AS bbb FROM rw_view1 WHERE aa<10;
+
+SELECT table_name, is_insertable_into
+  FROM information_schema.tables
+ WHERE table_name = 'rw_view2';
+
+SELECT table_name, is_updatable, is_insertable_into
+  FROM information_schema.views
+ WHERE table_name = 'rw_view2';
+
+SELECT table_name, column_name, is_updatable
+  FROM information_schema.columns
+ WHERE table_name = 'rw_view2'
+ ORDER BY ordinal_position;
+
+INSERT INTO rw_view2 VALUES (3, 'Row 3');
+INSERT INTO rw_view2 (aaa) VALUES (4);
+SELECT * FROM rw_view2;
+UPDATE rw_view2 SET bbb='Row 4' WHERE aaa=4;
+DELETE FROM rw_view2 WHERE aaa=2;
+SELECT * FROM rw_view2;
+
+EXPLAIN (costs off) UPDATE rw_view2 SET aaa=5 WHERE aaa=4;
+EXPLAIN (costs off) DELETE FROM rw_view2 WHERE aaa=4;
+
+DROP TABLE base_tbl CASCADE;
+
+-- view on top of view with rules
+
+CREATE TABLE base_tbl (a int PRIMARY KEY, b text DEFAULT 'Unspecified');
+INSERT INTO base_tbl SELECT i, 'Row ' || i FROM generate_series(-2, 2) g(i);
+
+CREATE VIEW rw_view1 AS SELECT * FROM base_tbl WHERE a>0 OFFSET 0; -- not updatable without rules/triggers
+CREATE VIEW rw_view2 AS SELECT * FROM rw_view1 WHERE a<10;
+
+SELECT table_name, is_insertable_into
+  FROM information_schema.tables
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+
+SELECT table_name, is_updatable, is_insertable_into
+  FROM information_schema.views
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+
+SELECT table_name, column_name, is_updatable
+  FROM information_schema.columns
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name, ordinal_position;
+
+CREATE RULE rw_view1_ins_rule AS ON INSERT TO rw_view1
+  DO INSTEAD INSERT INTO base_tbl VALUES (NEW.a, NEW.b) RETURNING *;
+
+SELECT table_name, is_insertable_into
+  FROM information_schema.tables
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+
+SELECT table_name, is_updatable, is_insertable_into
+  FROM information_schema.views
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+
+SELECT table_name, column_name, is_updatable
+  FROM information_schema.columns
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name, ordinal_position;
+
+CREATE RULE rw_view1_upd_rule AS ON UPDATE TO rw_view1
+  DO INSTEAD UPDATE base_tbl SET b=NEW.b WHERE a=OLD.a RETURNING NEW.*;
+
+SELECT table_name, is_insertable_into
+  FROM information_schema.tables
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+
+SELECT table_name, is_updatable, is_insertable_into
+  FROM information_schema.views
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+
+SELECT table_name, column_name, is_updatable
+  FROM information_schema.columns
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name, ordinal_position;
+
+CREATE RULE rw_view1_del_rule AS ON DELETE TO rw_view1
+  DO INSTEAD DELETE FROM base_tbl WHERE a=OLD.a RETURNING OLD.*;
+
+SELECT table_name, is_insertable_into
+  FROM information_schema.tables
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+
+SELECT table_name, is_updatable, is_insertable_into
+  FROM information_schema.views
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+
+SELECT table_name, column_name, is_updatable
+  FROM information_schema.columns
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name, ordinal_position;
+
+INSERT INTO rw_view2 VALUES (3, 'Row 3') RETURNING *;
+UPDATE rw_view2 SET b='Row three' WHERE a=3 RETURNING *;
+SELECT * FROM rw_view2;
+DELETE FROM rw_view2 WHERE a=3 RETURNING *;
+SELECT * FROM rw_view2;
+
+EXPLAIN (costs off) UPDATE rw_view2 SET a=3 WHERE a=2;
+EXPLAIN (costs off) DELETE FROM rw_view2 WHERE a=2;
+
+DROP TABLE base_tbl CASCADE;
+
+-- view on top of view with triggers
+
+CREATE TABLE base_tbl (a int PRIMARY KEY, b text DEFAULT 'Unspecified');
+INSERT INTO base_tbl SELECT i, 'Row ' || i FROM generate_series(-2, 2) g(i);
+
+CREATE VIEW rw_view1 AS SELECT * FROM base_tbl WHERE a>0 OFFSET 0; -- not updatable without rules/triggers
+CREATE VIEW rw_view2 AS SELECT * FROM rw_view1 WHERE a<10;
+
+SELECT table_name, is_insertable_into
+  FROM information_schema.tables
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+
+SELECT table_name, is_updatable, is_insertable_into,
+       is_trigger_updatable, is_trigger_deletable,
+       is_trigger_insertable_into
+  FROM information_schema.views
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+
+SELECT table_name, column_name, is_updatable
+  FROM information_schema.columns
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name, ordinal_position;
+
+CREATE FUNCTION rw_view1_trig_fn()
+RETURNS trigger AS
+$$
+BEGIN
+  IF TG_OP = 'INSERT' THEN
+    INSERT INTO base_tbl VALUES (NEW.a, NEW.b);
+    RETURN NEW;
+  ELSIF TG_OP = 'UPDATE' THEN
+    UPDATE base_tbl SET b=NEW.b WHERE a=OLD.a;
+    RETURN NEW;
+  ELSIF TG_OP = 'DELETE' THEN
+    DELETE FROM base_tbl WHERE a=OLD.a;
+    RETURN OLD;
+  END IF;
+END;
+$$
+LANGUAGE plpgsql;
+
+CREATE TRIGGER rw_view1_ins_trig INSTEAD OF INSERT ON rw_view1
+  FOR EACH ROW EXECUTE PROCEDURE rw_view1_trig_fn();
+
+SELECT table_name, is_insertable_into
+  FROM information_schema.tables
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+
+SELECT table_name, is_updatable, is_insertable_into,
+       is_trigger_updatable, is_trigger_deletable,
+       is_trigger_insertable_into
+  FROM information_schema.views
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+
+SELECT table_name, column_name, is_updatable
+  FROM information_schema.columns
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name, ordinal_position;
+
+CREATE TRIGGER rw_view1_upd_trig INSTEAD OF UPDATE ON rw_view1
+  FOR EACH ROW EXECUTE PROCEDURE rw_view1_trig_fn();
+
+SELECT table_name, is_insertable_into
+  FROM information_schema.tables
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+
+SELECT table_name, is_updatable, is_insertable_into,
+       is_trigger_updatable, is_trigger_deletable,
+       is_trigger_insertable_into
+  FROM information_schema.views
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+
+SELECT table_name, column_name, is_updatable
+  FROM information_schema.columns
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name, ordinal_position;
+
+CREATE TRIGGER rw_view1_del_trig INSTEAD OF DELETE ON rw_view1
+  FOR EACH ROW EXECUTE PROCEDURE rw_view1_trig_fn();
+
+SELECT table_name, is_insertable_into
+  FROM information_schema.tables
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+
+SELECT table_name, is_updatable, is_insertable_into,
+       is_trigger_updatable, is_trigger_deletable,
+       is_trigger_insertable_into
+  FROM information_schema.views
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name;
+
+SELECT table_name, column_name, is_updatable
+  FROM information_schema.columns
+ WHERE table_name LIKE 'rw_view%'
+ ORDER BY table_name, ordinal_position;
+
+INSERT INTO rw_view2 VALUES (3, 'Row 3') RETURNING *;
+UPDATE rw_view2 SET b='Row three' WHERE a=3 RETURNING *;
+SELECT * FROM rw_view2;
+DELETE FROM rw_view2 WHERE a=3 RETURNING *;
+SELECT * FROM rw_view2;
+
+EXPLAIN (costs off) UPDATE rw_view2 SET a=3 WHERE a=2;
+EXPLAIN (costs off) DELETE FROM rw_view2 WHERE a=2;
+
+DROP TABLE base_tbl CASCADE;
+DROP FUNCTION rw_view1_trig_fn();
+
+-- update using whole row from view
+
+CREATE TABLE base_tbl (a int PRIMARY KEY, b text DEFAULT 'Unspecified');
+INSERT INTO base_tbl SELECT i, 'Row ' || i FROM generate_series(-2, 2) g(i);
+
+CREATE VIEW rw_view1 AS SELECT b AS bb, a AS aa FROM base_tbl;
+
+CREATE FUNCTION rw_view1_aa(x rw_view1)
+  RETURNS int AS $$ SELECT x.aa $$ LANGUAGE sql;
+
+UPDATE rw_view1 v SET bb='Updated row 2' WHERE rw_view1_aa(v)=2
+  RETURNING rw_view1_aa(v), v.bb;
+SELECT * FROM base_tbl;
+
+EXPLAIN (costs off)
+UPDATE rw_view1 v SET bb='Updated row 2' WHERE rw_view1_aa(v)=2
+  RETURNING rw_view1_aa(v), v.bb;
+
+DROP TABLE base_tbl CASCADE;
+
+-- permissions checks
+
+CREATE USER view_user1;
+CREATE USER view_user2;
+
+SET SESSION AUTHORIZATION view_user1;
+CREATE TABLE base_tbl(a int, b text, c float);
+INSERT INTO base_tbl VALUES (1, 'Row 1', 1.0);
+CREATE VIEW rw_view1 AS SELECT b AS bb, c AS cc, a AS aa FROM base_tbl;
+INSERT INTO rw_view1 VALUES ('Row 2', 2.0, 2);
+
+GRANT SELECT ON base_tbl TO view_user2;
+GRANT SELECT ON rw_view1 TO view_user2;
+GRANT UPDATE (a,c) ON base_tbl TO view_user2;
+GRANT UPDATE (bb,cc) ON rw_view1 TO view_user2;
+RESET SESSION AUTHORIZATION;
+
+SET SESSION AUTHORIZATION view_user2;
+CREATE VIEW rw_view2 AS SELECT b AS bb, c AS cc, a AS aa FROM base_tbl;
+SELECT * FROM base_tbl; -- ok
+SELECT * FROM rw_view1; -- ok
+SELECT * FROM rw_view2; -- ok
+
+INSERT INTO base_tbl VALUES (3, 'Row 3', 3.0); -- not allowed
+INSERT INTO rw_view1 VALUES ('Row 3', 3.0, 3); -- not allowed
+INSERT INTO rw_view2 VALUES ('Row 3', 3.0, 3); -- not allowed
+
+UPDATE base_tbl SET a=a, c=c; -- ok
+UPDATE base_tbl SET b=b; -- not allowed
+UPDATE rw_view1 SET bb=bb, cc=cc; -- ok
+UPDATE rw_view1 SET aa=aa; -- not allowed
+UPDATE rw_view2 SET aa=aa, cc=cc; -- ok
+UPDATE rw_view2 SET bb=bb; -- not allowed
+
+DELETE FROM base_tbl; -- not allowed
+DELETE FROM rw_view1; -- not allowed
+DELETE FROM rw_view2; -- not allowed
+RESET SESSION AUTHORIZATION;
+
+SET SESSION AUTHORIZATION view_user1;
+GRANT INSERT, DELETE ON base_tbl TO view_user2;
+RESET SESSION AUTHORIZATION;
+
+SET SESSION AUTHORIZATION view_user2;
+INSERT INTO base_tbl VALUES (3, 'Row 3', 3.0); -- ok
+INSERT INTO rw_view1 VALUES ('Row 4', 4.0, 4); -- not allowed
+INSERT INTO rw_view2 VALUES ('Row 4', 4.0, 4); -- ok
+DELETE FROM base_tbl WHERE a=1; -- ok
+DELETE FROM rw_view1 WHERE aa=2; -- not allowed
+DELETE FROM rw_view2 WHERE aa=2; -- ok
+SELECT * FROM base_tbl;
+RESET SESSION AUTHORIZATION;
+
+SET SESSION AUTHORIZATION view_user1;
+REVOKE INSERT, DELETE ON base_tbl FROM view_user2;
+GRANT INSERT, DELETE ON rw_view1 TO view_user2;
+RESET SESSION AUTHORIZATION;
+
+SET SESSION AUTHORIZATION view_user2;
+INSERT INTO base_tbl VALUES (5, 'Row 5', 5.0); -- not allowed
+INSERT INTO rw_view1 VALUES ('Row 5', 5.0, 5); -- ok
+INSERT INTO rw_view2 VALUES ('Row 6', 6.0, 6); -- not allowed
+DELETE FROM base_tbl WHERE a=3; -- not allowed
+DELETE FROM rw_view1 WHERE aa=3; -- ok
+DELETE FROM rw_view2 WHERE aa=4; -- not allowed
+SELECT * FROM base_tbl;
+RESET SESSION AUTHORIZATION;
+
+DROP TABLE base_tbl CASCADE;
+
+DROP USER view_user1;
+DROP USER view_user2;
+
+-- column defaults
+
+CREATE TABLE base_tbl (a int PRIMARY KEY, b text DEFAULT 'Unspecified', c serial);
+INSERT INTO base_tbl VALUES (1, 'Row 1');
+INSERT INTO base_tbl VALUES (2, 'Row 2');
+INSERT INTO base_tbl VALUES (3);
+
+CREATE VIEW rw_view1 AS SELECT a AS aa, b AS bb FROM base_tbl;
+ALTER VIEW rw_view1 ALTER COLUMN bb SET DEFAULT 'View default';
+
+INSERT INTO rw_view1 VALUES (4, 'Row 4');
+INSERT INTO rw_view1 (aa) VALUES (5);
+
+SELECT * FROM base_tbl;
+
+DROP TABLE base_tbl CASCADE;
+
+-- Table having triggers
+
+CREATE TABLE base_tbl (a int PRIMARY KEY, b text DEFAULT 'Unspecified');
+INSERT INTO base_tbl VALUES (1, 'Row 1');
+INSERT INTO base_tbl VALUES (2, 'Row 2');
+
+CREATE FUNCTION rw_view1_trig_fn()
+RETURNS trigger AS
+$$
+BEGIN
+  IF TG_OP = 'INSERT' THEN
+    UPDATE base_tbl SET b=NEW.b WHERE a=1;
+    RETURN NULL;
+  END IF;
+  RETURN NULL;
+END;
+$$
+LANGUAGE plpgsql;
+
+CREATE TRIGGER rw_view1_ins_trig AFTER INSERT ON base_tbl
+  FOR EACH ROW EXECUTE PROCEDURE rw_view1_trig_fn();
+
+CREATE VIEW rw_view1 AS SELECT a AS aa, b AS bb FROM base_tbl;
+
+INSERT INTO rw_view1 VALUES (3, 'Row 3');
+select * from base_tbl;
+
+DROP VIEW rw_view1;
+DROP TRIGGER rw_view1_ins_trig on base_tbl;
+DROP FUNCTION rw_view1_trig_fn();
+DROP TABLE base_tbl;
+
+-- view with ORDER BY
+
+CREATE TABLE base_tbl (a int, b int);
+INSERT INTO base_tbl VALUES (1,2), (4,5), (3,-3);
+
+CREATE VIEW rw_view1 AS SELECT * FROM base_tbl ORDER BY a+b;
+
+SELECT * FROM rw_view1;
+
+INSERT INTO rw_view1 VALUES (7,-8);
+SELECT * FROM rw_view1;
+
+EXPLAIN (verbose, costs off) UPDATE rw_view1 SET b = b + 1 RETURNING *;
+UPDATE rw_view1 SET b = b + 1 RETURNING *;
+SELECT * FROM rw_view1;
+
+DROP TABLE base_tbl CASCADE;
+
+-- multiple array-column updates
+
+CREATE TABLE base_tbl (a int, arr int[]);
+INSERT INTO base_tbl VALUES (1,ARRAY[2]), (3,ARRAY[4]);
+
+CREATE VIEW rw_view1 AS SELECT * FROM base_tbl;
+
+UPDATE rw_view1 SET arr[1] = 42, arr[2] = 77 WHERE a = 3;
+
+SELECT * FROM rw_view1;
+
+DROP TABLE base_tbl CASCADE;