po 6. 2. 2023 v 0:25 odesÃlatel Corey Huinker <corey.huin...@gmail.com> napsal:
> >>> >>> Clearly, it is hard to write a regression test for an externally >>> volatile value. `SELECT sign(:BACKEND_PID)` would technically do the job, >>> if we're striving for completeness. >>> >> >> I did simple test - :BACKEND_PID should be equal pg_backend_pid() >> >> > > Even better. > > >> >>> >>> Do we want to change %p to pull from this variable and save the >>> snprintf()? Not a measurable savings, more or a don't-repeat-yourself thing. >>> >> >> I checked the code, and I don't think so. Current state is safer (I >> think). The psql's variables are not protected, and I think, so is safer, >> better to >> read the value for prompt directly by usage of the libpq API instead read >> the possibly "customized" variable. I see possible inconsistency, >> but again, the same inconsistency can be for variables USER and DBNAME >> too, and I am not able to say what is significantly better. Just prompt >> shows >> real value, and the related variable is +/- copy in connection time. >> >> I am not 100% sure in this area what is better, but the change requires >> wider and more general discussion, and I don't think the benefits of >> possible >> change are enough. There are just two possible solutions - we can protect >> some psql's variables (and it can do some compatibility issues), or we >> need to accept, so the value in prompt can be fake. It is better to not >> touch it :-). >> > > I agree it is out of scope of this patch, but I like the idea of protected > psql variables, and I doubt users are intentionally re-using these vars to > any positive effect. The more likely case is that newer psql vars just > happen to use the names chosen by somebody's script in the past. > bash variables are not protected too. I know this is in a different context, and different architecture. It can be a very simple patch, but it needs wider discussion. Probably it should be immutable, it is safer, and now I do not have any useful use case for mutability of these variables. Regards Pavel > > >> >> done >> >> >> > Everything passes. Docs look good. Test looks good. >
