Lester Caine wrote:

> Having now seen some statements about 'REPLACE' I think that we could
> make an argument that the MySQL process is correct in that your new
> record SHOULD replace the existing one and so perhaps the discussion
> there would be worth exploring as a DIFFERENT statement to the one
> currently proposed - with Jim's input on why the MySQL version breaks down.

However appropriate REPLACE is to headlamps or lug nuts, it's lousy in
databases. If you change a value unrelated to a unique or primary key
and there are referential constraints dependent on the unchanged key,
the referencing records should change or disappear. Nor should the
existence of referencing records cause the statement to fail - at the
end of the statement the constraint is valid.



Regards,


Ann