FORMS4.0 Question, relations between 3 blocks

Alan Lin <alanlin_at_thor.srl.caltech.edu> wrote:
>
>I am trying to build a form for our department's paper publication data.
>I have created three tables,
>
>paper:
> paper_id, title, journal, volume, number, page, year, ...
>
>author:
> author_id, last_name, first_name, ...
>
>publication:
> paper_id, author_num, author_id
> etc...

Your third block is based on a table that has author_id as its primary key, and is slave to a block that displays author_id's. So, each author_id from block b leads to one and only one record in block c. That's why your block c displays only one record at a time.

If you really need to display all the authors's names, you can't define block b as block c's master. Rather, you should define a where clause for block c that catches all authors in block b. One like this, for instance:

  author_id IN (select author_id from publication

                where paper_id = :block_a.paper_id)

Needless to say, you will need to write triggers to query block c for every change in block a, which is, in fact, the true master of block c.

If you have further questions, feel free to ask them.

Best regards Received on Fri Sep 29 1995 - 00:00:00 CET