Stuart, Thank you!
I will investigate. /s/jr Consultant Concerto GR Mobile: 612.208.6601 Concerto - a composition for orchestra and a soloist > On 29Aug, 2017, at 7:52 AM, Stuart Bishop <stu...@stuartbishop.net> wrote: > > On 29 August 2017 at 08:42, Jerry Regan > <jerry.re...@concertoglobalresources.com> wrote: >> Tom, >> >> After a few minutes thought….. >> >> /s/jr >> Consultant >> Concerto GR >> Mobile: 612.208.6601 >> >> Concerto - a composition for orchestra and a soloist >> >> >> >> On 28Aug, 2017, at 6:08 PM, Tom Lane <t...@sss.pgh.pa.us> wrote: >> >> "David G. Johnston" <david.g.johns...@gmail.com> writes: >> >> On Mon, Aug 28, 2017 at 1:28 PM, Jerry Regan < >> jerry.re...@concertoglobalresources.com> wrote: >> >> My concern is how, after LISTENing in psql, I can tell it what to do when >> the NOTItFY is received. >> >> >> As far as I am aware you cannot. >> >> >> Yes, and psql is not designed to do anything of its own accord, >> so I think the answer is really "use another program”. >> >> >> psql would be running on *nix. >> >> Let’s suppose for a moment that I piped the output of a psql instance to awk >> or some similar program, configured to detect the NOTIFY. That program would >> then spawn a process to actually perform the work, parameters being whatever >> is part of the NOTIFY. Both this psql instance and the awk script would be >> dedicated to this task. >> >> Given this is not intended in any way to be production quality code - in >> fact, it’s intended to deliver XML to the client server for validation >> (xmllint) in a development/test environment - do you see anything that >> clearly won’t work? Also, this would be a very low volume connection. >> Perhaps one NOTIFY in five minutes - or longer. >> >> Yes, it’s a hack. > > Or crib some code from > http://initd.org/psycopg/docs/advanced.html#async-notify or > https://godoc.org/github.com/lib/pq/listen_example , which is probably > less effort than assembling this collection of hacks and trying to > make it reliable. Most PostgreSQL APIs have support for notifications. > > > -- > Stuart Bishop <stu...@stuartbishop.net> > http://www.stuartbishop.net/
