update.out

--
-- UPDATE ... SET <col> = DEFAULT;
--
CREATE TABLE update_test (
    a   INT DEFAULT 10,
    b   INT,
    c   TEXT
);
CREATE TABLE upsert_test (
    a   INT PRIMARY KEY,
    b   TEXT
);
INSERT INTO update_test VALUES (5, 10, 'foo');
INSERT INTO update_test(b, a) VALUES (15, 10);
SELECT a,b,c FROM update_test ORDER BY a,b,c;
 a  | b  |  c  
----+----+-----
  5 | 10 | foo
 10 | 15 | 
(2 rows)

UPDATE update_test SET a = DEFAULT, b = DEFAULT;
SELECT a,b,c FROM update_test ORDER BY a,b,c;
 a  | b |  c  
----+---+-----
 10 |   | foo
 10 |   | 
(2 rows)

-- aliases for the UPDATE target table
UPDATE update_test AS t SET b = 10 WHERE t.a = 10;
SELECT a,b,c FROM update_test ORDER BY a,b,c;
 a  | b  |  c  
----+----+-----
 10 | 10 | foo
 10 | 10 | 
(2 rows)

UPDATE update_test t SET b = t.b + 10 WHERE t.a = 10;
SELECT a,b,c FROM update_test ORDER BY a,b,c;
 a  | b  |  c  
----+----+-----
 10 | 20 | foo
 10 | 20 | 
(2 rows)

--
-- Test VALUES in FROM
--
UPDATE update_test SET a=v.i FROM (VALUES(100, 20)) AS v(i, j)
  WHERE update_test.b = v.j;
SELECT a,b,c FROM update_test ORDER BY a,b,c;
  a  | b  |  c  
-----+----+-----
 100 | 20 | foo
 100 | 20 | 
(2 rows)

-- fail, wrong data type:
UPDATE update_test SET a = v.* FROM (VALUES(100, 20)) AS v(i, j)
  WHERE update_test.b = v.j;
ERROR:  column "a" is of type integer but expression is of type record
LINE 1: UPDATE update_test SET a = v.* FROM (VALUES(100, 20)) AS v(i...
                                   ^
HINT:  You will need to rewrite or cast the expression.
--
-- Test multiple-set-clause syntax
--
INSERT INTO update_test SELECT a,b+1,c FROM update_test;
SELECT * FROM update_test;
  a  | b  |  c  
-----+----+-----
 100 | 20 | foo
 100 | 20 | 
 100 | 21 | foo
 100 | 21 | 
(4 rows)

UPDATE update_test SET (c,b,a) = ('bugle', b+11, DEFAULT) WHERE c = 'foo';
SELECT a,b,c FROM update_test ORDER BY a,b,c;
  a  | b  |   c   
-----+----+-------
  10 | 31 | bugle
  10 | 32 | bugle
 100 | 20 | 
 100 | 21 | 
(4 rows)

UPDATE update_test SET (c,b) = ('car', a+b), a = a + 1 WHERE a = 10;
SELECT a,b,c FROM update_test ORDER BY a,b,c;
  a  | b  |  c  
-----+----+-----
  11 | 41 | car
  11 | 42 | car
 100 | 20 | 
 100 | 21 | 
(4 rows)

-- fail, multi assignment to same column:
UPDATE update_test SET (c,b) = ('car', a+b), b = a + 1 WHERE a = 10;
ERROR:  multiple assignments to same column "b"
-- uncorrelated sub-select:
UPDATE update_test
  SET (b,a) = (select a,b from update_test where b = 41 and c = 'car')
  WHERE a = 100 AND b = 20;
SELECT * FROM update_test;
  a  | b  |  c  
-----+----+-----
 100 | 21 | 
  11 | 41 | car
  11 | 42 | car
  41 | 11 | 
(4 rows)

-- correlated sub-select:
UPDATE update_test o
  SET (b,a) = (select a+1,b from update_test i
               where i.a=o.a and i.b=o.b and i.c is not distinct from o.c);
SELECT * FROM update_test;
 a  |  b  |  c  
----+-----+-----
 21 | 101 | 
 41 |  12 | car
 42 |  12 | car
 11 |  42 | 
(4 rows)

-- fail, multiple rows supplied:
UPDATE update_test SET (b,a) = (select a+1,b from update_test);
ERROR:  more than one row returned by a subquery used as an expression
-- set to null if no rows supplied:
UPDATE update_test SET (b,a) = (select a+1,b from update_test where a = 1000)
  WHERE a = 11;
SELECT * FROM update_test;
 a  |  b  |  c  
----+-----+-----
 21 | 101 | 
 41 |  12 | car
 42 |  12 | car
    |     | 
(4 rows)

-- if an alias for the target table is specified, don't allow references
-- to the original table name
UPDATE update_test AS t SET b = update_test.b + 10 WHERE t.a = 10;
ERROR:  invalid reference to FROM-clause entry for table "update_test"
LINE 1: UPDATE update_test AS t SET b = update_test.b + 10 WHERE t.a...
                                        ^
HINT:  Perhaps you meant to reference the table alias "t".
-- Make sure that we can update to a TOASTed value.
UPDATE update_test SET c = repeat('x', 10000) WHERE c = 'car';
SELECT a, b, char_length(c) FROM update_test;
 a  |  b  | char_length 
----+-----+-------------
 21 | 101 |            
    |     |            
 41 |  12 |       10000
 42 |  12 |       10000
(4 rows)

-- Test ON CONFLICT DO UPDATE
INSERT INTO upsert_test VALUES(1, 'Boo');
-- uncorrelated  sub-select:
WITH aaa AS (SELECT 1 AS a, 'Foo' AS b) INSERT INTO upsert_test
  VALUES (1, 'Bar') ON CONFLICT(a)
  DO UPDATE SET (b, a) = (SELECT b, a FROM aaa) RETURNING *;
ERROR:  modification of distribution columns in OnConflictUpdate is not supported
-- correlated sub-select:
INSERT INTO upsert_test VALUES (1, 'Baz') ON CONFLICT(a)
  DO UPDATE SET (b, a) = (SELECT b || ', Correlated', a from upsert_test i WHERE i.a = upsert_test.a)
  RETURNING *;
ERROR:  modification of distribution columns in OnConflictUpdate is not supported
-- correlated sub-select (EXCLUDED.* alias):
INSERT INTO upsert_test VALUES (1, 'Bat') ON CONFLICT(a)
  DO UPDATE SET (b, a) = (SELECT b || ', Excluded', a from upsert_test i WHERE i.a = excluded.a)
  RETURNING *;
ERROR:  modification of distribution columns in OnConflictUpdate is not supported
DROP TABLE update_test;
DROP TABLE upsert_test;