Re: Column Redaction

* Heikki Linnakangas (hlinnakangas(at)vmware(dot)com) wrote:
> On 10/10/2014 01:35 PM, Stephen Frost wrote:
> >Regarding functions, 'leakproof' functions should be alright to allow,
> >though Heikki brings up a good point regarding binary search being
> >possible in a plpgsql function (or even directly by a client). Of
> >course, that approach also requires that you have a specific item in
> >mind.
>
> It doesn't require that you have a specific item in mind. Binary
> search is cheap, O(log n). It's easy to write a function to do a
> binary search on a single item, passed as argument, and then apply
> that to all rows:
>
> SELECT binary_search_reveal(cardnumber) FROM redacted_table;

Note that your binary_search_reveal wouldn't be marked as leakproof and
therefore this wouldn't be allowed. If this was allowed, you'd simply
do "raise notice" inside the function and call it a day.

Thanks,

Stephen