>> to handle DROP dependency behaviors properly. (On reflection, maybe
>> better if it's "bernoulli(internal) returns tablesample_handler",
>> so as to guarantee that such a function doesn't create a conflict with
>> any user-defined function of the same name.)
>
> The probability of conflict seems high with the system() so yeah we'd need
> some kind of differentiator.
Maybe it would be even better to have something like bernoulli(tablesample)
where "tablesample" defined as pseudo-type like "trigger".
