At 05:51 AM 18/04/2007, you wrote:

> I have two questions:
> I'm working with three tables: Book, Author and Book_Author. When
>inserting a new book, I open the Author table and select the ones I want
>do associate with the book, and that will be put in the Book_Author
>table. To do that, I use this :
>
> qryBook_Author.Insert;
> qryBook_Author.FieldByName('BOOK_ID').AsInteger :=
>qryBook.FieldByName('BOOK_ID').AsInteger;
> qryBook_Author.FieldByName('AUTHOR_ID').AsInteger :=
>qryAuthor.FieldByName('AUTHOR_ID').AsInteger;
> qryBook_Author.Post;
>
> If I use this without entering all the not null fields, I get an
>error informing that the required fields cannot be null. Of course they
>can't, by I'm just using a Post, not a Commit !

Post writes the new record to the database. If the underlying INSERT
statement includes non-nullable fields that contain no values then
the Post will fail and you get an exception.

>Is it necessary that all the not null fields of the master table to
>be filled before I use a Post command ?

Yes.

> Nevertheless, if I fill the required fields, and try to use the code
>above, I get the error: "Problem in binding cursor". What's this about ?

It is about a reference to a record in an unavailable set. It may
have to do with attempting to masterlink a record to a set that has
been closed or is awaiting some action to resolve a prior
exception. Can't be more explicit without more information but,
before calling Insert on the Book_Author dataset, test to make sure
it is open.

If you are writing this intersection record "invisibly" then use the
BeforeInsert handler of the Book_Author dataset to apply the
non-nullable values. If the key value of this set is a generator
then use GeneratorLinks for that value.

Helen