>Cetin Thanks a lot for your answer.
>
>This is correct, but how can I cover the case if the incoming text file not having the correct structure ?
>
>How can I take this kind of error ?
>
>Thanks again
>Petros

I don't know anything that'd decide the structure is correct or not. Maybe you could do some regular expression parsing to decide. If that'd help use checkconstraints (By default constraints are not checked).
Cetin