Creating multiple Rules for on update - Mailing list pgsql-general

I have a view joining two tables with a (1 to 1) relationship.  I am trying to create two update
rules (1 rule for each table in the view).  To accomplish this I am trying (unsuccessfully) to use
the where condition syntax of the update rules.

Basically, I only want to update a table if the columns related to its tuple are altered.  If
possible, I don't want to update/touch a tuple from a table who's data remains unchanged.
However, the where conditions that I am using to make this distinction are giving the following
error:

"ERROR:  cannot update a view"
"HINT:  You need an unconditional ON UPDATE DO INSTEAD rule."

Ofcourse, if my understanding of the use of the rule's WHERE condition is why off base, I would be
enteresting in knowing the proper way it should be used.

Here are my sample table, view, and rule definitions: <rule are at the bottom>




CREATE SEQUENCE public.person_seq
INCREMENT BY 1
START WITH 1
;


CREATE TABLE public.person
(
id integer primary key not null
        default nextval('public.person_seq'),
name varchar(30) unique not null
)
;

ALTER SEQUENCE public.person_seq OWNED BY public.person.id;


CREATE TABLE public.husband
(
id integer primary key
       references person(id),
tiesize    integer    not null
)
;


CREATE OR REPLACE VIEW public.vhusband (id, name, tiesize)  AS
SELECT
    A.id, A.name, B.tiesize
FROM
    public.person as A
INNER JOIN
    public.husband as B
ON
    A.id = B.ID
;


CREATE OR REPLACE RULE
            vhusband_update_person
AS ON UPDATE TO
            public.vhusband
WHERE

-- this is where I am trying to constrain which table
-- gets updated. Since name in only in the person table.
    (NEW.name)<>(OLD.name)


DO INSTEAD
(
    UPDATE
        public.person
    SET
        name = NEW.name
    WHERE
        id = OLD.id
)
;

CREATE OR REPLACE RULE
            vhusband_update_husband
AS ON UPDATE TO
            public.vhusband
WHERE

-- this is where I am trying to constrain which table
-- gets updated. Since tiesize in only in the husband table.
    (NEW.tiesize)<>(OLD.tiesize)
DO INSTEAD
(
    UPDATE
        public.husband
    SET
        tiesize = NEW.tiesize
    WHERE
        id = OLD.id
)
;

Regards,

Richard Broersma Jr.