At 04:11 PM 07-02-01 -0500, you wrote:

>Hello Paul
>
>GeneratorLinks is to allow IBO to go ahead and get the
>ID of the record before the actual insert. This allows
>it to pass it along to Detail tables that could be connected
>and other things. You don't have to use it for positioning,
>I think you are talking about keylinks.
>
>I use the following trigger on my tables:
>
> create trigger TRGBEFINS_Customer for Customer
> active before insert position 0
> as
> DECLARE VARIABLE Temp_ID integer;
> begin
> if ((new.Cus_ID is NULL) or (new.cus_ID = 0)) then
> begin
> new.Cus_ID = gen_id (Gen_Customer_ID, 1);

END THE TRIGGER HERE !!!

The following code is !!!! dangerous !!!!. Generators operate right
outside the transaction context. In a multi-user environment, you are
certain to get PK violations. Don't do it!!!

> end else begin
> Temp_ID = gen_id(Gen_Customer_ID,0);
> if (new.CUS_ID > Temp_ID) then
> begin
> Temp_ID = gen_id(Gen_Customer_ID, new.Cus_ID-Temp_ID);
> end
> end
> end
>
>It will update your generator if necessary and also, make
>sure that the generator doesn't get behind if you inserted
>records that had IDs not derived from the generator.

If you are using a generator to populate a primary key, you should NEVER
try to insert rows where the PK comes from another source that **that**
generator.

To add a further note on GeneratorLinks, you should always use it when
inserting into a bi-directional dataset, rather than waiting until after
the insert has committed, to ensure that the KeyLinks will work
properly. Reserve the use of the trigger for external clients or scripts.

Helen




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