> Daniel L. Miller wrote:
>
> Howdy all.
>
> I understand how to use generators with before-insert triggers to
> provide simple auto-increment fields:
>
> NEW.ID = GEN_ID(G_CUSTOMER_ID, 1);
>
> Taking it a step further, I can check for a null value before
> incrementing the generator in the trigger - if for example I needed to
> assign the generator's value prior to the insert:
>
> IF (NEW.ID IS NULL) THEN
> NEW.ID = GEN_ID(G_CUSTOMER_ID, 1);
>
> My question now is how to handle "tinkering". Particularly when
> developing a new database/application, it's typical to add or change
> records without going through the "proper" procedures (for example, I
> use ibwebadmin, which forces an entry in primary key fields without
> checking the result of the before insert trigger). So the generator
> can get "behind" in its numbering.

they do not get "behind" - DO NOT TINKER - is my advice. WHat do you mean by
get behind? We'd all be in a dire mess if this were ever possible.

>
> If I want to implement "generator protection" - where should I place
> it? In the before-inserts, the after-updates, both, or elsewhere? Is
> this something I should keep in my production environment as a form of
> defensive programming? I'm envisioning something like (and I haven't
> tried this yet):
>
> DECLARE VARIABLE t_id INTEGER;
> DECLARE VARIABLE t_gen INTEGER;
> BEGIN
> SELECT MAX(id) FROM jobs INTO :t_id;
> t_gen = GEN_ID( g_job_id, 0 );
> IF ( t_id > t_gen ) THEN
> t_id = GEN_ID( g_job_id, ( t_id - t_gen ) );
> END
>
> --
> Daniel

forget you ever thought about using MAX calls anywhere. Leave it to the
generator.
Alan