Hi,
The suppress_redundant_updates_trigger() works incorrectly
on the table defined with "WITH_OIDS" option.
----------
(*) The latest 8.4devel tree without SE-PostgreSQL patch
postgres=# CREATE TABLE min_updates_test ( f1 text, f2 int, f3 int) with oids;
CREATE TABLE ^^^^^^^^^ <- Here is different from the regression test.
postgres=# INSERT INTO min_updates_test VALUES ('a',1,2),('b','2',null);
INSERT 0 2
postgres=# CREATE TRIGGER z_min_update BEFORE UPDATE ON min_updates_test FOR EACH ROW EXECUTE
PROCEDUREsuppress_redundant_updates_trigger();
CREATE TRIGGER
postgres=# UPDATE min_updates_test SET f1 = f1;
UPDATE 2
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The current version does not allow to update the "oid", so the older
value is preserved implicitly. However, it is done at heap_update().
Before-row-trigger functions are invoked before heap_update(), so
the field to store the "oid" is empty (InvalidOid) at the moment.
Then, suppress_redundant_updates_trigger() makes a decision there is
a difference between old and new versions.
It seems to me the older value has to be preserved just before
invocation of row-trigger functions.
Any comment?
Thanks,
--
OSS Platform Development Division, NEC
KaiGai Kohei <kaigai@ak.jp.nec.com>