2003-08-26 20:32:23 +02:00
|
|
|
--
|
|
|
|
-- UPDATE ... SET <col> = DEFAULT;
|
|
|
|
--
|
|
|
|
CREATE TABLE update_test (
|
|
|
|
a INT DEFAULT 10,
|
|
|
|
b INT
|
|
|
|
);
|
|
|
|
INSERT INTO update_test VALUES (5, 10);
|
|
|
|
INSERT INTO update_test VALUES (10, 15);
|
|
|
|
SELECT * FROM update_test;
|
|
|
|
a | b
|
|
|
|
----+----
|
|
|
|
5 | 10
|
|
|
|
10 | 15
|
|
|
|
(2 rows)
|
|
|
|
|
|
|
|
UPDATE update_test SET a = DEFAULT, b = DEFAULT;
|
|
|
|
SELECT * FROM update_test;
|
|
|
|
a | b
|
|
|
|
----+---
|
|
|
|
10 |
|
|
|
|
10 |
|
|
|
|
(2 rows)
|
|
|
|
|
2006-01-22 06:20:35 +01:00
|
|
|
-- aliases for the UPDATE target table
|
|
|
|
UPDATE update_test AS t SET b = 10 WHERE t.a = 10;
|
|
|
|
SELECT * FROM update_test;
|
|
|
|
a | b
|
|
|
|
----+----
|
|
|
|
10 | 10
|
|
|
|
10 | 10
|
|
|
|
(2 rows)
|
|
|
|
|
|
|
|
UPDATE update_test t SET b = t.b + 10 WHERE t.a = 10;
|
|
|
|
SELECT * FROM update_test;
|
|
|
|
a | b
|
|
|
|
----+----
|
|
|
|
10 | 20
|
|
|
|
10 | 20
|
|
|
|
(2 rows)
|
|
|
|
|
|
|
|
-- if an alias for the target table is specified, don't allow references
|
|
|
|
-- to the original table name
|
|
|
|
BEGIN;
|
|
|
|
SET LOCAL add_missing_from = false;
|
|
|
|
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"
|
|
|
|
HINT: Perhaps you meant to reference the table alias "t".
|
|
|
|
ROLLBACK;
|
2003-08-26 20:32:23 +02:00
|
|
|
DROP TABLE update_test;
|