Insert into view

Any thoughts on the following

------------------------------ testview.sql
-------------------------------------
drop table testhead; /* If it exists */
drop table testline; /* If it exists */
drop view testview; /* If it exists */

create table testhead (
  part text
);

create table testline (
  part text,
  colour text,
  adate datetime default 'now'
);

create view testview as
  select testhead.part, testline.colour, testline.adate from testhead, testline
  where testhead.part = testline.part;

insert into testview values  ('pen', 'green');
insert into testview values  ('pen', 'blue');
insert into testview values  ('pen', 'black');

select * from testview;

-----------------------------------------------------------------------------------

The inserts report no errors, and when looking into $PGDATA/base/mydb/testview
with a hex editor I can see the values inserted. 

The select on view returns nothing... 

Should the insert not fail seeing that views are read only ?

-- 
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Regards
Theo