I've looked for information on leakproofness of operators but haven't found anything can you direct me to a source of this information?
On Fri, Jul 24, 2020 at 3:40 PM Ted Toth <txt...@gmail.com> wrote: > > On Fri, Jul 24, 2020 at 3:15 PM Tom Lane <t...@sss.pgh.pa.us> wrote: > >> Ted Toth <txt...@gmail.com> writes: >> > I'm trying to understand when RLS select policy is applied so I created >> the >> > follow to test but I don't understand why the query filter order is >> > different for the 2 queries can anyone explain? >> >> The core reason why not is that the ~~ operator isn't considered >> leakproof. Plain text equality is leakproof, so it's safe to evaluate >> ahead of the RLS filter --- and we'd rather do so because the plpgsql >> function is assumed to be much more expensive than a built-in operator. >> >> (~~ isn't leakproof because it can throw errors that expose information >> about the pattern argument.) >> >> regards, tom lane >> > > Thanks for the explanation. > > Ted >
