At Mon, 22 Jun 2026 06:56:45 +0000, "Hayato Kuroda (Fujitsu)" <[email protected]> wrote in > Dear Peter, > > > Note that the latter includes pg_basebackup, pg_receivewal, and > > pg_recvlogical, which feel generally similar to pg_createsubscriber. > > Hmm, but similar command pg_upgrade was included in the server app page. > > The page [1] defined that server commands are the command can be run on the > same > server with the postgres server process. IIRC, the command was categorized as > "Server Application" because it assumed standby is running on the same > machine. > > But... I think the command is located on the border between the server and > the client. > We should hear other opinions too. > > [1]: https://www.postgresql.org/docs/devel/reference-server.html
I also agree that pg_createsubscriber sits somewhere on the boundary between server and client applications. If we were to draw a distinction, one possible interpretation would be that server applications are tools that access server resources beyond what a regular client connection normally does. That seems broadly consistent with the current classification, although pg_basebackup still feels somewhat borderline under that interpretation. I also wonder whether the server/client distinction is particularly important here. A number of utilities seem to fall somewhere between the two categories, and I'm not sure users pay much attention to that classification when looking up commands. Regards, -- Kyotaro Horiguchi NTT Open Source Software Center
