Data Validation via Required Fields Question

Is it possible to get from the BDE which fields of a table are "required"?
Also, when I try to post a record that does not have these fields, I get an
EDataBaseError exception but not an EDBEngineError.  Why is this?  Ideally,
when the user tries to post an "incomplete" record I would like to trap
this condition and give them the option of cancelling the insert/append
operation or returning to the form in question to fill in the fields.  Any
ideas would be greatly appreciated, the simpler the better of course.
Thanks in advance for any and all help, suggestions, ideas.
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Rob Tanner B.E.,B.Sc.
Design Engineer
WestBau Technologies, Inc.