Determining a table column by the view column.

[Dmitriy Igrishin <dmitigr@xxxxxxxxx>]

Hey all,

Is there way to determine a table column referenced by
a view column via SQL?

I want to create an universal function to determine
mandatoriness of some column of the view (i.e.
check the not null constraint of underlying table column).

Thanks.

-- 
// Dmitriy.