>1. Get rid of the empty record
>
>2. What do you use to provide this field uniqueness? NextID() idea?
>This is a table for horses and the uniqueness field idea is because a horse can only have one parent.

I actually was sure before that the horse (and any mammal for this matter, including humans) will have two parents :)

>BTW, why do you need Numeric 10? Will Integer work for you?
>because i need to related with the others tables with the same type of field.

If you don't want to change your database structure, you may leave Numeric.

Otherwise all PK/FK fields may be integer instead.