Hi Thanks, you solution works for most of the databases. But now I noticed that we have single 9.5 version also. And seems like this function *pg_size_bytes* came from 9.6
# psql -U postgres -Atc "select > pg_size_bytes(current_setting('shared_buffers'));" > ERROR: function pg_size_bytes(text) does not exist > LINE 1: select pg_size_bytes(current_setting('shared_buffers')); > ^ > HINT: No function matches the given name and argument types. You might > need to add explicit type casts. Do you perhaps happen to know a way how to get this to work in 9.5 also..? Thanks again. Regards Raul Kontakt Magnus Hagander (<mag...@hagander.net>) kirjutas kuupƤeval K, 14. oktoober 2020 kell 18:38: > > > On Wed, Oct 14, 2020 at 5:23 PM Tom Lane <t...@sss.pgh.pa.us> wrote: > >> Magnus Hagander <mag...@hagander.net> writes: >> > On Wed, Oct 14, 2020 at 5:10 PM Tom Lane <t...@sss.pgh.pa.us> wrote: >> >> It's fairly annoying that this doesn't work: >> >> regression=# select pg_size_bytes(setting||' '||unit) from pg_settings >> >> where name = 'shared_buffers'; >> >> > Actually thinking though, surely *this* particular case can be spelled >> as: >> > SELECT pg_size_bytes(current_setting('shared_buffers')) >> >> Yeah, that might be the most recommendable way. >> >> > Or if doing it off pg_settings: >> > SELECT setting::bigint * pg_size_bytes(unit) from pg_settings where >> > name='shared_buffers' >> >> No, because that will fail for any unit other than '8kB', eg >> >> regression=# select pg_size_bytes('MB'); >> ERROR: invalid size: "MB" >> > > Right, but it would certainly work for *this* case using pg_asettings, is > what I meant. > > That said, I think it'd then actually be better to teach pg_size_bytes to > know that "MB" is the same as "1MB" and parse that. That might be something > that would actually be useful in other cases as well -- basically as a way > to get conversion units in general. Basically if the string is "unit only" > then consider that as "1 unit". > > -- > Magnus Hagander > Me: https://www.hagander.net/ <http://www.hagander.net/> > Work: https://www.redpill-linpro.com/ <http://www.redpill-linpro.com/> >